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{{#Wiki_filter:FLORIDA POWER AND | {{#Wiki_filter:FLORIDA POWER AND LIGHTCOMPANY NUCLEAR ENGINEERING DEPARTMENT P.O. Box 14000 Juno Beach, Florida 33408 ST. LUCIE NUCLEAR PlANT, UNIT 2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATIONOF ALTERNATIVEEXAMINATION Prepared by Component, Support and Inspection Department Code Programs Group For St LucIe NucIear Power PIant 6501 South Hwy. A1A Jensen | ||
: Beach, Florida 34957 Commercial Service Date: | |||
USNRC Docket Number. | |||
Document Number. | |||
Revtsion Number. | |||
0 Date: | |||
August 8, 1983 50-389 PS L-200-AOA-94-1 September 28, 1994 4410200233 4l410iZ PDR ADQCK 05000389 9 | |||
= | |||
..PDR | |||
ISI NUCLEAR ENGINEERING Csl&ODE PROGRAMS P,.O. BOX 14000 JUNO BEACH, FLA 33408 (40'> eem181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL4004LDA4I4-1 Revhbn 0 | |||
Sephmbor 28, 1884 ABSTRACT Florida Power and Ught Company (FPL) has determined, based upon the results of previous examination documentation, that we are unable to completely satisfy the requirements for augmented reactor vessel shell weld examinations specified in 10 CFR 50.55a(g)(6)(il)(A) of the Code of Federal Regulations. | |||
This submittal provides the information to justify FPLs determination, supplemented by documentation required by the Commission to grant FPL's Request for Alternative Examinations for satisfying the St. Lucie Nuclear Power Plant, Unit 2, Augmented Reactor Vessel Shell Weld | This submittal provides the information to justify FPLs determination, supplemented by documentation required by the Commission to grant FPL's Request for Alternative Examinations for satisfying the St. Lucie Nuclear Power Plant, Unit 2, Augmented Reactor Vessel Shell Weld | ||
'xamination. | |||
The requirements | The requirements forthe augmented examination ofthe reactor vessel shell welds was conducted, during the First Inservice Inspection Interval, which began on August 8, 1983 and ended on August 8, 1993. | ||
The First Inservice Inspection (ISI) Program was developed based on the rules set forth in the ASME Boiler and Pressure Vessel Code, Section XI 1980 Edition through the Winter 1980 Addenda. | The First Inservice Inspection (ISI) Program was developed based on the rules set forth in the ASME Boiler and Pressure Vessel Code, Section XI 1980 Edition through the Winter 1980 Addenda. | ||
File USNRCA,OA | File USNRCA,OA Page 2 | ||
ISI NUCLEAR ENGINEERING OS!MODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA S$408 (407) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4 1 Revtabn 0 | |||
September 28, 1884 1.0 SCOPE FPL has made a determination that we are unable to completely. satisfy the requirements for augmented reactor vessel shell weld examinations specified in Title 10; Code of Federal Regulations, Part 50, Section 55a(g)(6)(ii)(A). | |||
This document as required by 10 CFR 50.55a(g)(ii)(A)(5), provides the information to support the determination and the proposed alternatives to the examination requirements that provide an acceptable level of quality and safety. | This document as required by 10 CFR 50.55a(g)(ii)(A)(5), provides the information to support the determination and the proposed alternatives to the examination requirements that provide an acceptable level of quality and safety. | ||
2.0 | 2.0 EXAMINATIONREQUIREMENTS FPL shall augment our reactor vessel examination by implementing once, as part of the inservice inspection interval in effect on September 8, 1992, the examination requirements for reactor vessel shell welds specified in Item B1.10 of Examination Category B-A, "Pressure Retaining Welds in Reactor Vessel, " in Table WB-2500-1 of subsection IWB of the 1989 Edition of Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code, subject to the conditions specified in 10 CFR 50.55a(g)(ii)(A)(3) and (4). | ||
FPL has elected not to defer the augmented examinations in accordance with 10 CFR 50.55a(g)(ii)(A)(3), and therefore the augmented examinations were performed in accordance with the related procedures specified in 1980 Edition through the Winter 1980 Addenda of Section XI, applicable to the St. Lucie | FPL has elected not to defer the augmented examinations in accordance with 10 CFR 50.55a(g)(ii)(A)(3), | ||
Table 2.1 below provides the examination requirements for the augmented reactor vessel shell welds for Examination Category B-A, Item B1.10, Table 2.1 EXAMINATIONCATEGORY B-A PRESSURE RETAINING WELDS IN REACTOR VESSEL Item | and therefore the augmented examinations were performed in accordance with the related procedures specified in 1980 Edition through the Winter 1980 Addenda of Section XI, applicable to the St. Lucie Unit2 First Inservice Inspection Interval in effect on September 8, 1992. | ||
Table 2.1 below provides the examination requirements for the augmented reactor vessel shell welds for Examination Category B-A, Item B1.10, Table 2.1 EXAMINATIONCATEGORY B-A PRESSURE RETAINING WELDS IN REACTOR VESSEL Item Parts No. | |||
Examined B1.10 Shell Welds Examination Requirements NIA Examination Method Volumetric Extent and Frequency of Examination AII Welds'1.11 CIrcumferentlal IWB-2500-1 Volumetric B1.12 Longitudinal IWB-2500-2 Volumetrfc Includes essentially 100% of the weld length All Welds'll Welds'ile USNRCAOA Page 3 | |||
ISI NUCLEAR ENGINEERING cslwoDE PRoGRAMs P.O. BOX 14000 JUNO BEACH, FLA | |||
,88408 (407) 8844181 ST. WCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAI. | |||
3.0 | REQUEST FOR AUTHOIUZATION OF ALTERNATIVE EXAMINATION PSL4004ClA4I4-1 Ravtabn 0 | ||
FPL is unable to satisfy the augmented reactor vessel shell weld examination requirement to essentially perform 100 percent examination coverage | SepSember 28, 1884 NOTE: | ||
For the purpose of the augmented examination of the reactor vessel, essentially 100 percent as used in Table IWB-2500-1 means more than 90 percent of the examination volume of each weld, where the reduction In coverage is due to interference by another component, or part g'eometry. | |||
3.0 AUGMENTED EXAMINATION The augmented examination of the reactor vessel is satisfied by an examination of essentially 100 percent of the reactor vessel shell welds specTiied in 10 CFR 50.55a(g)(6)(ii)(A)(2) that has been completed during the inservice inspection interval in effect on September 8, 1992. | |||
FPL is unable to satisfy the augmented reactor vessel shell weld examination requirement to essentially perform 100 percent examination coverage ofthe augmented reactor vessel shell welds specified in 10 CFR 50.55a (g)(6)(ii)(A)(2), because configuration and permanent attachments prohibit essentially 100% ultrasonic examination coverage of the required examination volume. | |||
Described below, coupled with the Tables and Figures, are details of the examination limitations by weld description. The accompanying Figures graphically depict the locations and extent of the limitations with respect to weld metal and associated base material. The Table quantifies the limitations in terms of present code required volume which was effectively covered. | Described below, coupled with the Tables and Figures, are details of the examination limitations by weld description. The accompanying Figures graphically depict the locations and extent of the limitations with respect to weld metal and associated base material. The Table quantifies the limitations in terms of present code required volume which was effectively covered. | ||
3.1 | 3.1 CIRCUMFERENTIALSHELL WELDS A. | ||
LOWER SHELL TO LOWER HEAD WELD The mechanized examination of the Lower Shell-to-Lower Head weld 201-141 of Figure IWB-2500-3, volume E-F-G-H is limited due to interference from the core support lugs and anti-rotation lugs. | |||
File USNRCAOA | Figure 1.1 is a roll out view showing the inaccessible scan surfaces from the vessel inside surface and shows the volume of material not examinable from the inside surface where scanning was limited by lug interference. | ||
INTERMEDIATESHELL TO LOWER SHELL WELD Examination of the Intermediate Shell-to-Lower Shell weld 101-171 of Figure IWB-2500-2, volume A-B-C-D is limited along the length of the weld due to interference from the material surveillance specimens. | |||
Figure 1.1 is a roll out view of weld 101-171 depicting areas where examination scans can not be performed. | |||
File USNRCAOA Page 4 | |||
e | e L | ||
1 | |||
~ E | |||
ISI NUCLEAR ENGINEERING CSIODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 6844181 ST. LIICIEUNIT2 RRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNAllVE EXAMINAlION PSL400~A4I4-1 RevhIon 0 Sap1ambor 28, 1884 C. | |||
3.2 | UPPER SHELL TO MIDDLESHELL WELD Examination of the Upper Shell-to-Middle Shell weld 106-121, of Figure IWB-2500-1, volume A-~D, volume is effectively examined 100% of the weld length without limitation. | ||
3.2 LONGITUDINALSHELL WELDS A. | |||
LOWER SHELL WELDS The examinations of the Lower Shell Vertical welds 101-142A, B and C of Figure IWB-2500-2, volume A-B-C-D, with the exception of 101-142C were essentially 100% examined for the length of the weld. The examination of weld 101-142C is limited due to interference of the surveillance capsules. | |||
The limitations are shown on Figure 1.1 and 1.5. | The limitations are shown on Figure 1.1 and 1.5. | ||
B. | B. | ||
C. UPPER SHELL WELDS Examination of the Upper Shell Vertical welds Figure IWB-2500-2, volume A-B-C-D, welds 101-122A, B, and C is limited by interference from the inlet nozzle inner radius blend and the outlet nozzle integral extension as shown on Figure 1.1. However, the examinations are complemented by the Nozzle-to-Shell weld examinations. | MIDDLESHELL WELDS Examinations ofthe Middle Shell Vertical welds Figure IWB-2500-2, volume A-B-C-D, welds 101-124A, and B volume is effectively examined 100% of the weld length without limitation. The examination of the Middle Shell Vertical welds 101-124C, is limited from one side by interference from the material surveillance capsules as shown on Figure 1.1. | ||
4.0 | C. | ||
File USNRCAOA | UPPER SHELL WELDS Examination of the Upper Shell Vertical welds Figure IWB-2500-2, volume A-B-C-D, welds 101-122A, B, and C is limited by interference from the inlet nozzle inner radius blend and the outlet nozzle integral extension as shown on Figure 1.1. | ||
However, the examinations are complemented by the Nozzle-to-Shell weld examinations. | |||
4.0 DISCUSSION 10 CFR 50.55a (g) (4), recognizes that throughout the service life of a nuclear power facility, components which are classified as ASME Code Class 1 shall meet the requirements, except design and access provisions requirements, set forth in Section XI, to the extent practical within the limitations of design, geometry and materials of construction of the components. | |||
File USNRCAOA Page 5 | |||
NUCLEAR ENQINEERINQ CSIODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 8844181 ST. WCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4-1 Rivichn 0 SOPI4rnber 28, 1884 4.1 NEW REGULATION 10 CFR 50.55a(g)(6)(II)(A) CHANGE The change in the regulation has little or no effect on the St. Lucie Nuclear Power Plant, Unit 2, First 10-Year Inservice Inspection Interval schedule examinations, as FPL performs essentially 100% volumetric examination of all reactor pressure vessel weld lengths, to the extent practical each inservice inspection interval. | |||
The last mechanized (automated) examination activity was performed during the 1989 refueling outage, which was part of the first inservice inspection interval In | The last mechanized (automated) examination activity was performed during the 1989 refueling outage, which was part of the first inservice inspection interval In | ||
.effect on September 8, 1992 when the rule change became effective. | |||
Because FPL inservice examinations were extended to Include essentially 100% | Because FPL inservice examinations were extended to Include essentially 100% | ||
of all reactor pressure vessel welds the augmented reactor vessel examination requirements of the rule change which became effective on September 8, 1992, meet the examination requirements for reactor vessel shell welds specified in Examination Item B1.10 of Examination Category B-A, "Pressure Retaining Welds in Reactor Vessel," in Table IWB-2500-1 of Subsection IWB of the 1989 Edition of Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code, and subject to the conditions specified in 10 CFR 50.55a(g)(6)(ii)(A)(3) and (4). | of all reactor pressure vessel welds the augmented reactor vessel examination requirements of the rule change which became effective on September 8, 1992, meet the examination requirements for reactor vessel shell welds specified in Examination Item B1.10 of Examination Category B-A, "Pressure Retaining Welds in Reactor Vessel," in Table IWB-2500-1 of Subsection IWB of the 1989 Edition of Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code, and subject to the conditions specified in 10 CFR 50.55a(g)(6)(ii)(A)(3) and (4). | ||
4.2 | 4.2 FIRST INSPECTION INTERVAL During the 1989 refueling outage, of the St. Lucie Nuclear Power Plant, Unit 2, First Inservice Inspection Interval, Southwest Research Institute (SwRI) using their Enhanced Data Acquisition System performed the Reactor Pressure Vessel mechanized (automated) ultrasonic examinations. | ||
These examinations covered the essentially 100% of all Reactor Pressure Vessel shell circumferiental and longitudinal welds, to the extent practical within the design, geometry and materials of construction. | |||
These examinations were conducted to satisfy the requirements of the 1980 Edition through the Winter 1980 Addenda of Section XI. In addition to the 80W80 Code requirements, the mechanized examination activity was extended to include all Reactor Pressure Vessel accessible weld lengths. | These examinations were conducted to satisfy the requirements of the 1980 Edition through the Winter 1980 Addenda of Section XI. In addition to the 80W80 Code requirements, the mechanized examination activity was extended to include all Reactor Pressure Vessel accessible weld lengths. | ||
NOTE: i | NOTE: i It is the intent of FPL to use the First Inservice Inspection interval examinations to satisfy the augmented examination requirements of the rule change. | ||
4.3 | 4.3 NDE EXAMINATIONPROCEDURES NDE examination procedures implemented during the St. Lucie Unit 2 Reactor Pressure Vessel examinations utilized the 1980 Edition through the Winter 1980 ASME Section XI Code-specified ultrasonic techniques. | ||
These techniques were File USNRCA,OA Page 6 | |||
NUCLEAR ENQINEERINQ CSINODg PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA | |||
$8408 (401) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL RECIUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL4004C)A84 1 | |||
4.4 | Revtebn 0 | ||
SepRmber 28, 1884 augmented by special SwRI qualified examination techniques to obtain full coverage of the near surface and underclad material volumes. | |||
A | 4.4 EXAMINATIONCOVERAGE All of the RPV welds were examined for 100% of accessible weld lengths, The flowskirt, core barrel lugs, and material specimen tubes limited fulllength scanning access to some welds. The outlet nozzle integral extensions and fiange-to-skell weld joint configuration limited fullcoverage of some weld volumes by all ultrasonic | ||
,examination techniques. | |||
A fullvee path calibration of the 45'hear wave scan was used to compensate for limitations encountered in the near surface and those due to geometric shadowing. | |||
A 50/70'i-modal ultrasonic examination was used for examination of the Inner 25 percent t. | A 50/70'i-modal ultrasonic examination was used for examination of the Inner 25 percent t. | ||
Examination limitations were reported in detail as required by USNRC Regulatory Guide 1.150, Revision 1. Weld examinations where 90% or greater coverage of the volume was achieved are considered as having met essentially 100% | Examination limitations were reported in detail as required by USNRC Regulatory Guide 1.150, Revision 1. Weld examinations where 90% or greater coverage of the volume was achieved are considered as having met essentially 100% | ||
requirement as used in Table IWB-2500-1 of the ASME Code. | requirement as used in Table IWB-2500-1 of the ASME Code. | ||
Examination limitations which received less that 90% coverage, as required by Code Case N-460 were documented in the form of a Request for Relief and submitted as part of the 'St. Lucie Unit 2 Second Inservice Inspection Interval Update Program Submittal. | Examination limitations which received less that 90% coverage, as required by Code Case N-460 were documented in the form of a Request for Relief and submitted as part of the 'St. Lucie Unit 2 Second Inservice Inspection Interval Update Program Submittal. | ||
NOTE: | NOTE: | ||
It should be noted that electronic gating does not result in any examination limitations since the entire instrument screen presentation is monitored during the examinations, video taped, and reviewed independently following the examinations. | |||
Attachment B provides Tables of all augmented examination percent of coverage for those welds which fall within the augmented examination requirements of the regulation. The peIcent of coverage Included in Attachment B provides the coverage for all applicable welds, whether or not the coverage achieved was greater or less than 90% as stated in Code Case N-460. | Attachment B provides Tables of all augmented examination percent of coverage for those welds which fall within the augmented examination requirements of the regulation. The peIcent of coverage Included in Attachment B provides the coverage for all applicable welds, whether or not the coverage achieved was greater or less than 90% as stated in Code Case N-460. | ||
4.5 | 4.5 CODE CASE NQ60 Code coverage requirements, as allowed by Code Case NQ60 is implemented by FPL on vessels as follows: | ||
File USNRCAOA | File USNRCAOA Page 7 | ||
ISI NUCLEAR ENQINEERINQ CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 8844181 ST. LUCIE UNrr 2 RRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION Of ALTERNATiVE EXAMINATION PSL400~A84 1 | |||
Revkbn 0 Sepiember 28, 1884 The 0'amination scan is intended to be utilized once to Identity conditions which may interfere with the examination of the weld and the required volume (1/2t). Coverage with this search unit is not factored into the overall calculation of weld coverage. | |||
2. | |||
The required examination angles are 0', 45'/2 vee path, and 60'/2 vee path. Of these, the two angle beams applied in two directions parallel with the weld and in two directions perpendicular to the weld are factored into the calculation. Except in cases where the beam is oriented essentially perpendicular to the plane of postulated flaws, the 0'xamination contributes nothing to the examinations, therefore, it is not factored Into the calculation. | |||
3. | |||
FPL elected to add enhancements to the overall examination of the reactor pressure vessel, as follows: | |||
FPL was one of the first utilities to implement the regulatory guide when | a. | ||
File USNRCAOA | A full vee path 45'o enhance the examination of the area directly under the cladding and to reduce areas of non coverage due to scan limitations. | ||
b. | |||
A special bi-modal scan of the cladding-base metal interface and 1/4 t under the cladding. This was not factored into the coverage calculations, except to augment weld examinations where clad roughness exhibited near. surface noise. | |||
4. | |||
The overall coverage calculation consists of an average of the 45'nd 60'xaminations in all four directions. | |||
4.6 USNRC REGULATORY GUIDE 1.150 Regulatory Guide 1.150, Ultrasonic Testing of Reactor Vessel Welds During Preservice and Inservice Examinations was also used during the examination activity. | |||
FPL was one of the first utilities to implement the regulatory guide when itwas still in the draft mode. FPL along with its vendor, SwRI held several meetings with the USNRC prior to implementation. The last St. Lucie mechanized Reactor Pressure Vessel Examination activity was conducted during the 1989 refueling outage, and FPL implemented Regulatory Guide 1.150, Rev. 1. Appendix A, provides FPL's position for compliance with Regulatory Guide 1.150. | |||
File USNRCAOA Page 8 | |||
NUCLEAR ENQINEERINQ CSINODE PROQRAMS P.O. BOX 14000 JUNO BEACH, FLA | |||
$8408 (407) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4-1 Recon 0 | |||
Seplamber 28, 1884 4.7 OTHER CONSIDERATIONS As required by IWB-2200, FPL determined prior to the performance of the preservice examinations that the examination of the reactor pressure vessel will be conducted from the inside surface ofthe vessel, utilizing mechanized ultrasonic equipment and with techniques equivalent to those that are expected to be employed for subsequent inservice examinations. This decision was made based on the following criteria: | |||
1. | |||
access for the inspector, examination personnel and equipment necessaly to conduct the examinations; 2. | |||
Because of the limited access between the vessel and bioshield wall, conducting the examinations from the external surface for the purpose of investigating the small amount of weld volume missed during the mechanized inside surface examinations would require the desttuction of the insulation during the removal process, excessive manhours, manrem, and substantial costs without providing any substantial increase in the quality and safety of the unit. | Sufficient space for removal and storage of structural members (vessel internalS, shielding and insulation; 3. | ||
5.0 | installation and support of handling equipment (e.g., hoists) to facilitate removal, disassembly and storage of equipment. | ||
Because of the limited access between the vessel and bioshield wall, conducting the examinations from the external surface for the purpose of investigating the small amount of weld volume missed during the mechanized inside surface examinations would require the desttuction of the insulation during the removal | |||
: process, excessive | |||
: manhours, manrem, and substantial costs without providing any substantial increase in the quality and safety of the unit. | |||
5.0 ALTERNATIVEEXAMINATIONSOR TESTS: | |||
The extent of examination volume achieved ultrasonically and the alternate scans performed (see Examination Coverage Table Attachment B) coupled with the system pressure tests provide assurance of an acceptable level of quality and safety. As an alternative FPL performed the following: | The extent of examination volume achieved ultrasonically and the alternate scans performed (see Examination Coverage Table Attachment B) coupled with the system pressure tests provide assurance of an acceptable level of quality and safety. As an alternative FPL performed the following: | ||
1) | |||
Periodic System Pressure tests per Category B-P, Table IWB-2500-1 2) | |||
Conduct essentially 100% Mechanized (automated) Ultrasonic Examinations to the extent practical on all reactor pressure vessel welds from the inside surface. | |||
3) 50/70'i-modal ultrasonic examination of the inner 25 percent t. | |||
4) | |||
Conduct a full vee 45'hear wave examination to the extent practical to compensate for recorded limitations. | |||
5) | |||
Employ as they become available additional examinations, inspections and/or techniques that would provide a substantial increase in the examination of areas File USNRCA,OA Page 9 | |||
ISI NUCLEAR ENGINEERINQ CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 33408 (407) 6844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZAlloN OF ALTERNATIVE EXAuINATION PSL400~A4I4-1 Ravlabn 0 SepIember 28, 1884 currently missed under current examination techniques. | |||
==6.0 IMPLEMENTATIONSCHEDULE== | ==6.0 IMPLEMENTATIONSCHEDULE== | ||
First Inservice Inspection Interval - August 08, 1983 to August 07, 1993 7.0 | First Inservice Inspection Interval - August 08, 1983 to August 07, 1993 7.0 ATTACHMENTSTO THE SUBMITTAL Attachment A Implementation of Regulatory Guide 1.150 Attachment B Percent of Coverage Tables Attachment C Examination Umitation Drawings. | ||
File USNRGA,OA | File USNRGA,OA Page 10 | ||
NUCLEAR ENQINEERINQ CSIODE PROQRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 6844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4 1 Reviake 0 | |||
Se PIember 28, 1884 ATTACHMENTA IMPLEMENTATIONOF REGULATORY GUIDE 1.150 File USNRCAOA Page 11 | |||
NUCLEAR ENGlNEERING DEPARTMENT COMPONENT, SUPPORT AND INSPECTIONS DEPARTMENT P.O. Box 14000 JUNO BEACH, FLORIDA | NUCLEAR ENGlNEERING DEPARTMENT COMPONENT, SUPPORT AND INSPECTIONS DEPARTMENT P.O. Box 14000 JUNO BEACH, FLORIDA 33408 St. Lucle Nuclear Power Plant Unit 2 SECOND INSERVICE INSPECTION INTERVAL SECOND INSPECTION PERIOD IMPLEMENTATIONOF REGULATORY GUIDE 1.150 Prepared by Florida Power and Ught Company Code Programs Group For St. Lucie Nuclear Power Plant 10 Miles South of Ft. Pierce on A1A Ft. Pierce, Florida 33034 Commercial Service Date: | ||
NRC Docket Number: | |||
Document Number. | |||
Revision Number. | |||
August 8, 1983 50-389 PSL-RG 1.150 0 | |||
Date: September 28, 1994 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 ABSTRACT This document provides a summary of how Florida Power and Light Company (FPL), | ||
implements fhe tequirements | implements fhe tequirements ofRegulafoty Guide 1. 150. FPL has complied, to the extent practical with the requirements of this regulatory guide for over 10 years. FPL, and our vendor Southwest Research Institute (SwRi), has conducted examinations on the reactor pressure vessels at bofh sifes (Sf. Lucie and Turkey Point), and on all four units (PSL-1 and 2, PTN 3 and 4). | ||
Where required in fhis document SwRi isinserted, in place | Where required in fhis document SwRi isinserted, in place ofFPL, fo make a disfincfion between equipment, techniques, or documentafion unique to SwRI. | ||
The mechanized ultrasonic examinations for the St. Lucie Nuclear Power Plant, Unit 2, Reactor Pressure Vesselis cunenfly scheduled fo be performedin fhe Second Inspection Period, of the Second Inspection Interval. The examinations will be conducted in accordance with the Amencan Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI, 1989 Edition, no Addenda, and fhe additional requirements of Regulatory Guide 1. 150 as stated within. | The mechanized ultrasonic examinations for the St. Lucie Nuclear Power Plant, Unit 2, Reactor Pressure Vesselis cunenfly scheduled fo be performedin fhe Second Inspection Period, of the Second Inspection Interval. The examinations will be conducted in accordance with the Amencan Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section XI, 1989 Edition, no Addenda, and fhe additional requirements of Regulatory Guide 1. 150 as stated within. | ||
This documentis | This documentis writtenin a format fhat firsidentifie the regulatory guide requitement, followed by a summary ofhow FPL willimplement that requitement. | ||
File RG1.150 | File RG1.150 Page 2 | ||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 INTRODUCTION Ultrasonic examination of the St. Lucie, Unit 2 reactor pressure vessel welds, Including the closure head will be performed during the upcoming Second Inservice Inspection Interval, in accordance with the 1989 Edition of the American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code (B&PVC), Section XI, and as supplemented by the additional requirements of Regulatory Guide 1.150, Revision 1. This document summarizes the additional requirements that Florida Power and LightCompany (FPL) implemented during previous examination activities in order to comply with the Regulatory Guide requirements. | ||
1.0 | FPL expects that these additional requirements willnot change. | ||
1.0 INSPECTION SYSTEM PERFORMANCE CHECKS The conduct of nondestructive examinations require that the performance characteristics of the Inspection system used be well defined and documented. | |||
This is particularly true for situations which require comparisons of examination results generated during successive examinations on the same components. An inspection system comprises of the following: | This is particularly true for situations which require comparisons of examination results generated during successive examinations on the same components. An inspection system comprises of the following: | ||
a. | |||
a transducer (search unit); | |||
b. | |||
The checks described in paragraphs 1.1 and 1.2 should be made | a single-channel instrument or each channel of a multichannel instrument; and c. | ||
a given cable type and length. | |||
The checks described in paragraphs 1.1 and 1.2 should be made forany ultrasonic (UT) system used for inspection of reactor pressure vessel (RPV) welds. | |||
The field performance checks described in 1.2 (with the possible exception of 1.2.c) should be conducted on a basic calibration block that represents the thickness range to be examined. | The field performance checks described in 1.2 (with the possible exception of 1.2.c) should be conducted on a basic calibration block that represents the thickness range to be examined. | ||
FPL agrees with the need to define and document the performance characteristics | FPL agrees with the need to define and document the performance characteristics ofUT systems, and we have been, and requiring our vendors (SwRl) to do so formany years. | ||
Most of the checks identliied herein are considered standard operating practice. FPL applies these requirements to all reactor vessel weld examinations, whether the examinations are manual, | Most of the checks identliied herein are considered standard operating practice. FPL applies these requirements to all reactor vessel weld examinations, whether the examinations are manual, orautomated (Mechanized) from the inside surface. Since the results of the field performance checks described in 1.2 are independent of calibration block design, FPL approved vendor's procedures are required to allow the use of any calibration block that willprovide the signal responses needed forthe performance check. | ||
File RG1.150 | File RG1.150 Page 3 | ||
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 Preexamina5on Performance Checks a. | |||
Frequency of Checks These checks should be verified within six (6)'months before reactor pressure vessel examinations performed during one outage. Pulse shape and noise suppression controls should remain at the same settings during calibration and, examination. | |||
b. | |||
FPL requires vendors not only to record RF pulse waveform asidentified above, but also requires the determination of the frequency spectrum and distance amplitude curve for each search unit used. Search units that do not meet strict | RF Waveform Arecord ofthe RF (radiofrequency) pulse waveform from a reference reflector should be obtained for each search unit used in the examination in a manner which will provide frequency amplitude information. At the highest amplitude portion of the beam, the RF return signal should be recorded before it has been rectified or conditioned for display. The reflector used in generating the RF return signal as well as the electronic system (i.e., the basic ultrasonic instrument, gating, and form of gated signal) should be documented. | ||
In addition to the analysis described above, FPL also requires photographs | These records should be used for comparison with previous and future records. | ||
1.2 | FPL requires vendors not only to record RF pulse waveform asidentified above, but also requires the determination of the frequency spectrum and distance amplitude curve for each search unit used. Search units that do not meet strict performance tolerances are prohibited from use. Documentation ofthis analysis is submitted to FPL priorto the performance ofthe examinations and are included as part of the final report of the examination activity. | ||
In addition to the analysis described above, FPL also requires photographs ofthe RF waveformin the field during initiaand finalcalibrations. This provides a record ofthe RF waveform obtained using the specific system components (transducer, instrument, and cable) that are used for calibration and examination. | |||
File RG1.150 | 1.2 Field Performance Checks a. | ||
Frequency of Checks As a minimum, these checks should be verified on site before and after examining all the welds that need to be examined in a reactor pressure vessel during one outage. | |||
Pulse shape and noise suppression controls should remain at the same settings during examination and calibration. | |||
File RG1.150 Page 4 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1884 Instrument Sensitivity During Llnearlty Checks The initial instrument sensitivity during the performance of 1.2,e should be such that it falls at the calibration sensitivity or at some point between the calibration sensitivity and the scanning sensitivity. | ||
RF Waveform | RF Waveform Arecord ofthe RF (radiofrequency) pulse waveform from a reference reflector should be obtained and recorded in a manner that will permit extraction of frequency amplitude information. At the highest amplitude portion of the beam, the RF return signal should be recorded before it has been rectified or conditioned for display.. This should be determined on the same reflector as that used in 1.1.b above. This record should be retained for future reference. | ||
d. | |||
Screen Height LInearity Screen height linearity of the ultrasonic instrument should be determined according to the mandatory Appendix I to Article 4, Section V of the ASME'ode or Appendix I to Section XI of the ASME Code. | |||
e. | |||
Amplitude Control Unearlty Amplitude control linearity should be determined according to the mandatory Appendix II ofArticle 4, Section V, of the ASME Code or Appendix I of Section XI of the ASME Code. | |||
Angle Beam Prone Charactertzatlon The vertical beam proflile should be determined for each search unit used during the examination by a procedure similar to that outlined in nonmandatory Appendix B-60, Article 4, Section V, of the ASME Code or Appendix I to Section XI of the ASME Code. Beam profile curves should be determined at different depths to cover the thicknesses of materials to be examined. Interpolation may be used to obtain beam profile correction for assessing flaws at intermediate depths for which beam profile has not been determined. | Angle Beam Prone Charactertzatlon The vertical beam proflile should be determined for each search unit used during the examination by a procedure similar to that outlined in nonmandatory Appendix B-60, Article 4, Section V, of the ASME Code or Appendix I to Section XI of the ASME Code. Beam profile curves should be determined at different depths to cover the thicknesses of materials to be examined. Interpolation may be used to obtain beam profile correction for assessing flaws at intermediate depths for which beam profile has not been determined. | ||
Beam profile measurements should be made at the sensitivity required for sizing. For example, sizing to 20-percent DAC criteria requires that the beam profile be determined at 20-percent DAC. | Beam profile measurements should be made at the sensitivity required for sizing. For example, sizing to 20-percent DAC criteria requires that the beam profile be determined at 20-percent DAC. | ||
File RG1.150 | File RG1.150 Page 5 | ||
il SECOND INSPECTION INTERVAL | il SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 The field performance checks described above are performed as follows: | ||
(1) | (1) | ||
(2) | RF Wavef'ann - Photographs ofthe RF waveformin the field during each initial and final calibration. This provides a record of fhe RF waveform obfained using the specific system components (transducer, instrument, and cable) that are used forcalibration and examination. | ||
p) | (2) | ||
In the case | Scraen height Lineanfy - Screen height linearity checks are performed for each instrument in accordance with the Regulatory Guiderequirements. Thesechecksare performedimmediafelybefore and after complefion ofthe examinations. | ||
Paragraph 1.2.b above requires that the instrument sensitivity during the performance of amplitude control linearify checks should be af the calibrafion sensitivity or scanning sensitivity. However, the calibrafion sensitivity levels (and scanning sensitivity levels) vary with the different techniques used during vessel examinations. Therefore, vendors are required fo perform these linearity checks at the extreme upper and lower ends of fhe sensitivity range. This ensures fhat fhe instrument is linear across a wide range of calibrafion and screening sensitivify levels. | p) | ||
In fhe case | Amplitude Control Linearity - Amplitude control linearity checks establish a linear relationship befween an adjusfment ofthe gain, or sensitivity, controls (knobs orswitches) and the conssponding signal amplitude change observed on the CRT. | ||
File RG1.150 | In the case ofmanual examinations in accordance with Regulatory Guide 1.150, amplifude control linearity is determined for each instrument in accordance with the Regulatory Guide requirements. | ||
These checks are performedin conjunction wifhthe screen height lineanfy checksimmediately before and after completion offhe examinafions. | |||
Paragraph 1.2.b above requires that the instrument sensitivity during the performance of amplitude control linearify checks should be af the calibrafion sensitivity or scanning sensitivity. However, the calibrafion sensitivity levels (and scanning sensitivity levels) vary with the different techniques used during vessel examinations. | |||
Therefore, vendors are required fo perform these linearity checks at the extreme upper and lower ends of fhe sensitivity range. | |||
This ensures fhat fhe instrument is linear across a wide range of calibrafion and screening sensitivify levels. | |||
In fhe case ofautomated examinafions, Gain Control circuity electronically compensafes forthe normal signal affenuatI'on that causes a sloping DAC curve and provides a variable gain adjustment across the CRT screen such that a consfant, horizontal DACcurveis attained. Gain Control performance is periodically verified on site during examinafions to assure that a straight horizontal DACis maintained. In essence, whenever the amplitude controls are used forindication amplitude measurements, amplitude confrollinearity checks are performed. | |||
File RG1.150 Page 6 | |||
I SECOND INSPECTION INTERVAL | I SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28. 1994 (4) | ||
Angle-Beam Profile Characfenzation-Abeam profile foreach single element pulse-echo angle beam search unitis determined on sifein accordance with the Regulatory Guide requirements. | |||
These profiles are generated using the 1/4, M', and 3/4T side-drilled holes in a calibration block that is as thick or thicker than the component to which the search unit will be applied. | |||
Since Appendix A of the Regulatory Guide permits sizing at either 2096 or 5096 of DAC, Vendors are required to take both 2096 and 5096 beam profiles. | |||
With the use of tandem dual-refracted longifudinal wave units for near surface examination, typical sizing methodologies are not applicable because of the unique search unit performance. | With the use of tandem dual-refracted longifudinal wave units for near surface examination, typical sizing methodologies are not applicable because of the unique search unit performance. | ||
Therefore, when near surface indications are observed with these techniques, special supplemental sizing techniques may be required depending upon the observed characteristi of fhe flaw These special supplemental sizing techniques have been substantiated and qualified using mockups, | Therefore, when near surface indications are observed with these techniques, special supplemental sizing techniques may be required depending upon the observed characteristi of fhe flaw These special supplemental sizing techniques have been substantiated and qualified using mockups, fieldexpenence, and research project data over many years. | ||
2.0 | 2.0 CAUBRATION System calibration should be performed to establish the DAC curve and the sweep range calibration in accordance with Article 4, Section V, of the ASME Code or Appendix I to Section XI. Calibration should be confirmed before and after each RPV examination, or each week in which the system is in use, whichever is less. | ||
Where possible, the same calibration block should be used for successive inservice examinations of the RPV. | Where | ||
: possible, the same calibration block should be used for successive inservice examinations of the RPV. | |||
FPL requires system calibration be performed on site in accordance with Regulatory Guide requirements on fhe applicable basic calibration block. | FPL requires system calibration be performed on site in accordance with Regulatory Guide requirements on fhe applicable basic calibration block. | ||
Calibration confirmation during manual examinations is performed prior to the examination; af least every four hours dunng fhe examinations; with any substitution of search unit, cable, or power source; and upon completion of the examinations. | Calibration confirmation during manual examinations is performed prior to the examination; af least every four hours dunng fhe examinations; with any substitution of search unit, cable, or power source; and upon completion of the examinations. | ||
For mechanized examinations, FPL requires calibration confirmation prior to the start of a series of examinations (a series is considered to be similar examinations performed using the same examinafion techniques and the same equipment configuration); with any substitution | For mechanized examinations, FPL requires calibration confirmation prior to the start of a series of examinations (a series is considered to be similar examinations performed using the same examinafion techniques and the same equipment configuration); with any substitution ofsearch unif, cable, orpower source; whenever the device is removed from the examination area; at leasf every week durin the examinafions; and at fhe completion of a series of examinafions. | ||
File RG1.150 | File RG1.150 Page 7 | ||
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 NOTE: | |||
2.1 | While this calibration confirmation frequency is consistent with the Regulatory Guide, itsometimes does not comply withthe 12-hour frequency requirements of paragraph T-432.1.2 of Section V. The acceptability of exceeding the Section V 12-hour calibration check can be demonstrated as allowed in paragraph IWA-2240 of Section XI. | ||
As required above, vendors are requin:d to use static calibration and static sizing techniques | 2.1 Calibration for Manual Scanning For manual sizing of flaws, static calibration may be used if sizing Is performed using a static transducer. | ||
When signals are maximized during calibration, they should also be maximized during sizing. For manual scanning for the detection of flaws, reference hole detection should be shown at scanning speed and detection level set accordingly. | |||
As required above, vendors are requin:d to use static calibration and static sizing techniques formanual examinations, maximizing both calibration and flawsignals. | |||
Reference hole detection is verified by scanning over the calibration block at the maximum scanning speed and verifying that the signal meets or exceeds the recording level. | Reference hole detection is verified by scanning over the calibration block at the maximum scanning speed and verifying that the signal meets or exceeds the recording level. | ||
2.2 | 2.2 Calibra5on for Mechanized Scanning When flaw detection is to be done by mechanized equipment, the calibration should be performed using the following guidelines: | ||
a. | |||
The DAC curve should be established using either a moving transducer mounted on the mechanism that will be used for examination of the component or a mechanism that duplicates the critical factors (e.g., | |||
C. The direction of transducer movement ( | transducer mounting, weight, pivot points, couplant) present in the scanning mechanism. | ||
b. | |||
Calibration speed should be at or higher than the scanning speed, except when correction factors established in 2.2.d are used. | |||
C. | |||
The direction of transducer movement (forward or backward) during calibration to establish the DAC curve should be the same direction during scanning unless it can be shown that a change in scanning direction does not reduce flaw detection capability. | |||
One of the following alternative guidelines should be=followed to establish correction factors if static basic calibration is used: | One of the following alternative guidelines should be=followed to establish correction factors if static basic calibration is used: | ||
(1) | (1) | ||
Correction factors between dynamic and static response should be established using the basic calibration block or, File RG1.150 Page 8 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 (2) | ||
FPL complies with these requiremenfs | Correction factors should be established using models and taking scaling factors into consideration (assumed scaling relationship should be verified) or, (3) | ||
2.3 | Correction factors should be established using full-scale mockups. | ||
When an electronic simulator is used | FPL complies with these requiremenfs forcalibration formechanized scanning in accordance wifh2.2.d(1) in that we have repeatedly required SeRI to demonstrate equivalency between the scanning with fhe PaR devices and fhe sfafic calibration techniques. | ||
FPL also requires SwRi to provide a report documenting this equivalency using the equipment perfl'nent to FPL's application. | |||
2.3 Callbra5on Confirmation Calibration confirmation performed as midshift or interim confirmation between onsite calibrations should comply with stability requirements in T-433, Article 4, Section V, of the ASME Code. | |||
C. Measures should be taken to ensure that the different variables such as temperature, vibration, and shock limits are minimized by controlling packaging, handling, and storage. | When an electronic simulator is used foronsite calibration confirmation after a Code required block calibration performed off site, the following should also apply: | ||
File RG1.150 | a. | ||
Complete system performance should be maintained stable prior to offsite calibrations and onsite calibration confirmation by use oftarget reflectors. The target reflectors should be mounted with identical physical displacement in both the offsite calibration facilities and the onsite mechanized equipment. | |||
Each onsite periodic calibration should be preceded by complete system performance verification using a minimum of two (2) target reflectors separated by a distance representing 75 percent of maximum thickness to be examined. | |||
b. | |||
Written records of calibrations should be established for both target reflector responses and Code calibration block DAC curves for each transducer. These written records may be used to monitor driftsince the original recorded calibration. | |||
C. | |||
Measures should be taken to ensure that the different variables such as temperature, vibration, and shock limits are minimized by controlling packaging, handling, and storage. | |||
File RG1.150 Page 9 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSLWG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1884 FPL requires calibration confirmation be performed at the frequency specified in paragraph 2 above and in compliance with the stability requirements of the Regulatory Guide. Vendors are required to perform the calibration confirmatio on site during using the basic calibration block, not an electronic block simulator. As such, the additional requirements identified in this paragraph for the use of an electronic block simulator do not apply. | ||
In addition to periodic calibration confinnations functional checks | In addition to periodic calibration confinnations functional checks of the UT instruments and the gain control circuitry system are typically performed at shift changeover. | ||
For full vessel examinations using the SwRi Fast PaR systems, two Data Acquisitions Systems are utilized in parallel. While one system is used for scanning and data acquisition, the other system is being calibrated for the next series of examinations. In effect, two separate cable system are used, one for calibration and another | These checks utilize electronic signal generators to monitor for changesin sweep and amplitude displays. The stabilitycriteria ofparagraph T-433 ofArtIcie 4 are used for acceptability of these functional checks. | ||
2.4 | For full vessel examinations using the SwRi Fast PaR | ||
: systems, two Data Acquisitions Systems are utilized in parallel. | |||
While one system is used for scanning and data acquisition, the other system is being calibrated for the next series of examinations. | |||
In effect, two separate cable system are used, one for calibration and another forexaminations. SwRI's Remote Cable Calibrator system allo~s comparison of the diiference in cable performance and also provides electronic signal generation forperiodic verification that the performance ofthe two cable systems has not changed. | |||
These cable performance checks are performed at the same time, and using the same criteria, as the electronic functional checks described above. | |||
2.4 Calibratton Blocks Calibration blocks should comply with Appendix I to Section XI or Article 4, Section V of the ASME Code. When an alternative calibration block or a new conventional block is used, a ratio between the DAC curves obtained from the original block and from the new block should be noted (for reference) to provide for a meaningful comparison or previous and current data. | |||
The calibration side-drilled holes in the basic calibration block and the block surface should be protected so that their characteristics do not change during storage. These side-drilled holes or the block surface should not be modified in any way (e.g., by polishing) between successive examinations. | The calibration side-drilled holes in the basic calibration block and the block surface should be protected so that their characteristics do not change during storage. These side-drilled holes or the block surface should not be modified in any way (e.g., by polishing) between successive examinations. | ||
Ifthe block surface or the calibration reflector holes have been polished by any chemical or mechanical means, this fact should be recorded. | |||
File RG1.150 | File RG1.150 Page 10 | ||
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1894 3.0 EXAMINATlON The scope and extent of the ultrasonic examinations should comply with IWA-2000, Section XI, of the ASME Code. | |||
If electronic gating is used to define the examination'olume within which indications are recorded the start and stop control points should Include the entire required thickness including the material near each surface. | If electronic gating is used to define the examination'olume within which indications are recorded the start and stop control points should Include the entire required thickness including the material near each surface. | ||
If a single gate is used, it should be capable of recording multiple indications appearing in the gate. Alternative means of recording may be used providing they do not reduce flaw detection and recording capability. | If a single gate is used, it should be capable of recording multiple indications appearing in the gate. Alternative means of recording may be used providing they do not reduce flaw detection and recording capability. | ||
Examination should be done with a minimum 25-percent scan overlap based on the transducer element size. | Examination should be done with a minimum 25-percent scan overlap based on the transducer element size. | ||
The scope and extent | The scope and extent ofmanual examinations are addressedin the examination plan and examination procedure in accordance wifh IWA-2000. | ||
In order to assure that the scope and extent ofaufomafed examinations comply with IlVA-2000 of Section XI, FPI requires the vendor to prepare a defailed Scan Plan for each automated examination activityin addition to typical examination procedures. This plan addresses device configurations, scanning parameters, calibration parameters, gate seffings, and other speciiicinformation needed to perform the work. Implementation of fhe scan plan, as prepared for a specific application, | In order to assure that the scope and extent ofaufomafed examinations comply with IlVA-2000 of Section XI, FPI requires the vendor to prepare a defailed Scan Plan for each automated examination activityin addition to typical examination procedures. | ||
The electronic gating system ufilized by vendors does not | This plan addresses device configurations, scanning parameters, calibration parameters, gate seffings, and other speciiicinformation needed to perform the work. Implementation of fhe scan plan, as prepared for a specific application, willensure that the full volume of the ASME examination area are examined to the extent allowed by the vessel conligurafion. Coverageis accomplished using a combination ofseveral beam angles and examination techniques as specified in fhe scan plans. | ||
The SwRI enhanced data acquisition system has overlapping electronic gating | The electronic gating system ufilized by vendors does not limifthe examination volume within whichindications are recorded. When the standard data acquisition systemis used, a video recovering is made of the acfual UTinsfrumenfs CRT presentations wifh the search unit positional informafion superimposed in real time. | ||
The SwRI enhanced data acquisition system has overlapping electronic gating foreach UTchannel such that a fullvolume examinationis digitized, recorded, and displayed. The enhanced data acquisition system gafing is capable ofrecording mulfiple simultaneous indications. | |||
Allexaminations performedin accordance with the regulatory guide are performed using a 25-percent overlap, unless a greater overlap is required. | Allexaminations performedin accordance with the regulatory guide are performed using a 25-percent overlap, unless a greater overlap is required. | ||
File RG1.150 | File RG1.150 Page 11 | ||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 3.1 INTERNALSURFACE The capability to effectively detect defects at the internal clad/base metal interface shall be considered acceptable if the examination procedures(s) or techniques meet the requirements of section 6.0 of this document and demonstrates the following: | ||
procedure for examination from the outer surface, or when using full vee from the inside surface, should include the use | procedure for examination from the outer surface, or when using full vee from the inside surface, should include the use ofthe 2-percent notch which penetrates the internal (clad) surface of the calibration blocks, defined by Section XI, Appendix I, Figure l-3131, or Section V, Article 4, T-434-1. | ||
Procedures | Procedures forexamination from the internal surface when not using the full vee should conform to paragraph 3.1.b below. | ||
b. | |||
an alternate reflector, other than the 2-percent notch described above, may be used provided (1) that it is located at the clad/base metal interface or at an equivalent distance from the surface, (2) that it does not exceed the maximum allowable defect size, and (3) that equivalent or superior results can be demonstrated. | |||
Procedures | c. | ||
Procedures | the examination procedures should provide the volumetric examination of at least 1 inch of metal as measured perpendicular to the nominal location of the base metal cladding interface. | ||
File RG1.150 | Procedures forexamination from the outside surface ofthe vessel walluse the 2-percent notch forreference as specifiedin paragraph 3.1(a). These procedures also include a half vee calibration with the notch used for calibration ofallindications which appear at the inside surface ofthe examination area. | ||
Procedures fortandem examinations fiom the inside surface utilizes 1!16 inch diameter side-drilled holes at the clad/base metal interface as descnbed in paragraph | |||
: 3. 1(b). In both cases, procedures provide for volumetric examination ofgreater than 1-inch depth below the claddinginterface as required byparagraph 3.1(c). SwRI has demonstrated that the reference sensitivity established on the 1!16 inch diameter side drilled holes meets or exceeds that specified in Section XIofthe ASME Code. This technique has also been demonstrated to have the capabi%ty of detecting flaws with good signal-to-noise discrimination at depths ofat least 2-3!4 inches below the clad-to-base metal interface, thus overiapping the through-wall zone of calibrated sensitivity of the 45 degree and 60 degree beams. Using the tandem beam transducers, SwRI has detected flaws ofminute size in the area between the clad-to-base metal interface and the first 45 degree and 60 degree dac point. | |||
File RG1.150 Page 12 | |||
"I | "I SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVIsION 0 REGULATORY GUIDE 1.150 September 28, 1994 FPL has also used 70 degree dual (side-by-side mounted piezoelectric elements) search units for underclad examinations; however, the useful range is limited to approximately 1 inch of depth below the cladding with no discernible improvement over the tandem beam search unit at the clad-to-base metal interface. | ||
SECOND INSPECTION INTERVAL | 3.2 ScannIng Weld-Metal Interface The beam angles used to scan welds should be based on the geometry of the weld/parent metal interface. Where feasible for welds such as those Identified in Section T-441.4.2 of Article 4, Section V, of the ASME Code, at least one angle should be such that the beam is perpendicular | ||
3.2 | (+ or - 15 degrees to the perpendicular) to the weld/parent metal interface, or should be demonstrated that unfavorably orientated planar flaws can be detected by UT technique being used. | ||
lfthis is not feasible, use of alternative volumetric NDE techniques, as permitted by the ASME Code, should be considered. | |||
For RPV shell seam welds, FPL uses the nominal Code-specified 0<egree, 4°ree, and 60<egree, beams to examine the full volume of the wall section except for the volume | For RPV shell seam welds, FPL uses the nominal Code-specified 0<egree, 4°ree, and 60<egree, beams to examine the full volume of the wall section except for the volume ofmaterial near the beam entry point, forwhich we use the previously mentioned tandem search units. | ||
Section T-441.4.2 (or T-441.3.2.2 | Section T-441.4.2 (or T-441.3.2.2 ofArticle 4, Section V, states that beam angles other than O-degree, 45-degree, and 60-degree should be used for the examination of (a) flange welds when fhe examinafion is conducfed from the flange face, (b) nozzle and nozzle welds when fhe examinafion is conducted, from fhe nozzle bore, (c) attachment and support welds, and (d) examinafion ofdouble faperjuncfions, FPL has employed this approach for many years. | ||
FPL and FPL approved vendors procedures, however, often provide more than Code-specified coverage where feasible. Each | FPL and FPL approved vendors procedures, however, often provide more than Code-specified coverage where feasible. Each offhe unique weld configurations nofed above is evaluafed to determine the best and most comprehensive coverage affainable. Mfhere necessary, other angle and straight beam examinations are performed fo assure complete coverage ofnozzle-to-shell, vessel-fo-fiange, and affachmen welds. P 8 viouslyment/oned tandem beam techniques are also utilized to provide the required near surface coverage when nozzle bore examinations are performed. | ||
4. | |||
File RG1.150 | BEAM PROFILE Delete entire paragraph. This section included in Recommended Change 1.2.f, Angle 8earri Profile Characterization. | ||
File RG1.150 Page 13 | |||
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 5. | |||
SCANNING WELD-METALINTERFACE 6. | |||
Delete entire paragraph. | |||
The difference befween joint configuration, plate thicknesses, fiaw locations within the we/d, fiaw orientafions, and acousfic characferisfics of the component mafenal a/I contnbufe to the inherent | This section Included in Recommended Change 3.2, Scanning Weld-Metal Interface. | ||
6.1 | RECORDING AND SIZING The capability to detect, record, and size the flaws delineated by Section XI, IWB-3500, should be demonstrated. The measurement tolerance established should be applied when sizing flaws detected and recorded during scanning (see paragraph 7.a). | ||
The difference befween joint configuration, plate thicknesses, fiaw locations within the we/d, fiaw orientafions, and acousfic characferisfics of the component mafenal a/I contnbufe to the inherent variabilityofsizing techniques. FPL has used and willcontinue to use, Code and non-Code sizing techniques, the use ofsupplemental NOE techniques ifpracfical, mockups of the particular configuratio, and when required, consultanfs to fullyevaluafe fhe examination and the results. | |||
6.1 Geomehh Indicathns Indications determined to be from geometric sources need not be sized. | |||
Recording of these indications should be at 50-percent DAC. When indications are evaluated as geometric in origin, the basis for that determination should be described. After recording sufficient information to identify the origin of the geometric indication, further recording and evaluation are not required. | Recording of these indications should be at 50-percent DAC. When indications are evaluated as geometric in origin, the basis for that determination should be described. After recording sufficient information to identify the origin of the geometric indication, further recording and evaluation are not required. | ||
Indication analysis and sizing are performed by FPL or FPL approved vendors. All the examination data is given an administrative and technical review by a FPL qualified NDE Level II andlor Level III, cerfr'fied in that particular method. | Indication analysis and sizing are performed by FPL or FPL approved vendors. All the examination data is given an administrative and technical review by a FPL qualified NDE Level II andlor Level III, cerfr'fied in that particular method. | ||
Indications that are geomefricin origin an: recorded at 50-percent DAC and the nature of each such indication is documenfed. | Indications that are geomefricin origin an: recorded at 50-percent DAC and the nature of each such indication is documenfed. | ||
6.2 | 6.2 indications with Changing Metal Path Indications that change metal path distances (including through-wall dimension), when scanned in accordance with the requirements of ASME Section XIfor a distance greater than that recorded from the calibration reflector, should be recorded. | ||
File RG1.150 | File RG1.150 Page 14 | ||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL PSLWG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 b. | ||
Reflectors which are at metal paths representing 25 percent and greater of the through-wall thickness of the vessel wall measured from the inner surface should be recorded in accordance with the requirements of the ASME Section XI and characterized at 50-percent DAC. | |||
Reflectors which are within the inner 25 percent of the through-wall thickness should be recorded at 20 percent DAC. Characterization should be in accordance with the demonstrated methods under paragraph 6.0. When the indication is sized at 20 percent DAC, this size may be corrected by subtracting the beam width in the through-thickness direction obtained from the calibration hole (between 20 percent DAC points) which is at a depth similar to the flaw depth. If the indication exceeds 50 percent DAC, the length should be recorded by measuring the distance between 50 percent DAC levels. | Reflectors which are within the inner 25 percent of the through-wall thickness should be recorded at 20 percent DAC. Characterization should be in accordance with the demonstrated methods under paragraph 6.0. When the indication is sized at 20 percent DAC, this size may be corrected by subtracting the beam width in the through-thickness direction obtained from the calibration hole (between 20 percent DAC points) which is at a depth similar to the flaw depth. If the indication exceeds 50 percent DAC, the length should be recorded by measuring the distance between 50 percent DAC levels. | ||
The determined size should be the larger of the two. | The determined size should be the larger of the two. | ||
FPL believes that theintent | FPL believes that theintent ofthis paragraphis to require the examiner to determine and document the most accurate size of a refiector having through-wall dimension, to the extent practicable. | ||
FPL typically requires both 20 percent and 50 percent beam spread measurement at the time of calibration in case the information is required during data analysis. | FPL typically requires both 20 percent and 50 percent beam spread measurement at the time of calibration in case the information is required during data analysis. | ||
For tandem beam search units, the use ofbeam spread conection | For tandem beam search units, the use ofbeam spread conection forsizing is not normally applicable because of the unique beam profile characteristics. | ||
In general, FPL concurs with the specified approach, but also requires application | When near surfaceindications are observed during a vessel examination, FPL routinely applies one or more special sizing techniques, before comparing the size to the acceptance criteria of Secfion XI. | ||
6.3 | In general, FPL concurs with the specified approach, but also requires application ofselected alternate sizing techniques when necessary based upon a | ||
case-by-case evaluation in determining which technique is considered most appropriate for the anticipated flaw type and orientatio. | |||
File RG1.150 | 6.3 Indication WIthout Changing Metal Path a. | ||
Indications which do not change metal path distance when scanned in accordance with the requirements of ASME Section XI and are within the outer 75 percent of the through-wall dimension should be recorded when any continuous dimension exceeds 1 inch. | |||
File RG1.150 Page 15 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGULATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1884 b. | ||
Ifthe indication falls within the inner 25 percent of the through-wall dimensions, it should be recorded ar 20 percent DAC and evaluated at 50 percent DAC. | |||
c. | |||
at SO degrees. Multiple scans, however, may reveal that these indications are traveling indications. If so, recording and sizing are to be done in accordance with paragraph 6.2. | Precautionary note: Indications lying parallel to welds may appear nontraveling (without changing metal path) when scanned by parallel moving transducers whose beams are aimed normal to the weld, i.e., | ||
at SO degrees. | |||
Multiple scans, | |||
: however, may reveal that these indications are traveling indications. If so, recording and sizing are to be done in accordance with paragraph 6.2. | |||
To the extent pracficable, evaluation ofnontravelingindicafionsis per/ormed in accordance with these requirements, along with the use of additional sizing techniques where appropriate. | To the extent pracficable, evaluation ofnontravelingindicafionsis per/ormed in accordance with these requirements, along with the use of additional sizing techniques where appropriate. | ||
The precautionary note | The precautionary note ofparagraph 6.3.cis appropriate. | ||
To alleviafe this concern, scanning is performed in the direction of the beam component wherever possible. | |||
6.4 | In those instances when this preferred mode of scanning cannot be utilized, NDE procedures address this concern by requiring additional scans (along the sound beam direction) of any nongeomefric angle beam indication observed during scans made parallel fo the weld. Additionalscans are performed using small scanincrements(or | ||
a, | /arge transducer overiap) in order to develop a very accurate data sef. | ||
6.4 Additional Recording Criteria The followinginformation should also be recorded forindications that are reportable according to this regulatory position: | |||
File RG1.150 | a, Indications should be recorded at scan intervals no greater than 1/4 inch. | ||
b. | |||
The recorded information should Include the indication travel (metal path distance) and the transducer position for 20 percent (where applicable), 50 percent, and 100 percent DAC and the maximum amplitude of the signal. | |||
File RG1.150 Page 16 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGUlATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1994 When multichannel equipment is used in the examination system such as that all examination displays are not available for simultaneous viewing, an electronic gating system should be used which will provide on-line, reportable, | ||
'recorded information regarding metal path, amplitude, and position of all indications exceeding a preset level. The preset level should be the minimum recording level required. To ensure that all recordable indications are | |||
The information required in Paragraph 6.4.b is | : recorded, a preferred method would incorporate multigates in each channel or a single gate for each channel with multI-Indication recording capability. | ||
In reference fo Paragraph 6.4.c which addresses the use | In reference fo Paragraph 6.4.a, initial scanning is af 25 percent overiap as specr'fied iParagraph 3. However, data to be utilized for specific sizing or invesfigation of indicafions that exceed the allowable limifsof Section XIis acquired at 1/4 inch scan intervals. | ||
The information required in Paragraph 6.4.b is typicallyrecorded for all vessel examinafions, whether the examination is performed manually or using automated equipment. | |||
instrument screens. Since fhe entire screen presentationis recorded, simulfaneousmultiplesignalsarerecorded asencountered. Thedafa analysis pmcess also includes review of all of the video tape dafa thereby ensuring that each recorded signal is reviewed and | In reference fo Paragraph 6.4.c which addresses the use ofmulti-channel equipmenf, the standard data acquisition system utilized by SeRI satisfie this requirement by virtue ofthe video recordr'ng offhe | ||
~ instrument screens. Since fhe entire screen presentationis recorded, simulfaneousmultiplesignalsarerecorded asencountered. | |||
Thedafa analysis pmcess also includes review of all of the video tape dafa thereby ensuring that each recorded signal is reviewed and | |||
Fife RG1.150 | .analyzed. | ||
7. | |||
REPORTING OF RESULTS Records obtained while followingthe recommendations of regulatory position 1.2, 3, and 6, along with discussions and explanations, ifany, should be kept available at the site. Ifthe size of an indication, as determined in regulatory position 6.2 or 6.3, exceeds the allowable limits of Section XI of the ASME Code, the indications should be reported as abnormal degradation of reactor pressure boundary in accordance with the recommendation of regulatory position 2.a(3) of Regulatory Guide 1.16. | |||
Fife RG1.150 Page 17 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGULATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1984 Along with the report of ultrasonic examination test | ||
: results, the following information should also be included: | |||
a. | |||
The best estimate of the tolerances in sizing the flaws at the Sensitivity required in Section 6 and the basis for this estimate. | |||
This estimate may be determined in part by the use of additional reflectors in the basic calibration block. | This estimate may be determined in part by the use of additional reflectors in the basic calibration block. | ||
b. | |||
A description of the technique used to qualify the effectiveness of the examination procedure, including, as a | |||
: minimum, material, section thickness, and reflectors. | |||
The best estimates of the portion of the volume required to be examined by the ASME Code that has not been effectively examined such as volumes of material near each surface because of near-field or other effects, volumes near interfaces between cladding and parent metal, volumes shadowed by laminar defects, volumes shadowed by part geometry, volumes inaccessible to the transducer, volumes affected by electronic gating, and volumes near the surface opposite the transducer. | The best estimates of the portion of the volume required to be examined by the ASME Code that has not been effectively examined such as volumes of material near each surface because of near-field or other effects, volumes near interfaces between cladding and parent metal, volumes shadowed by laminar defects, volumes shadowed by part geometry, volumes inaccessible to the transducer, volumes affected by electronic gating, and volumes near the surface opposite the transducer. | ||
Sketches and/or descriptions | Sketches and/or descriptions ofthe tools, fixtures, and component geometry which contribute to incomplete coverage should be included. | ||
d. | |||
Provide sketches of equipment (i.e., scanning mechanism and transducer holders) with reference points and necessary dimensions to allow a reviewer to follow the equipment's indication location scheme. | |||
In reference to Paragraph 7.a, FPL feels that the sizes obtained using Code sizing techniques should be used consistently for companson to Code acceptance standards whenever possible. Based on experience, Code sizing techniques appear to be somewhat conservative; however, there is little evidence to support the | e. | ||
When other volumetric techniques are used, a description ofthe techniques used should be included in the report. | |||
In reference to Paragraph 7.a, FPL feels that the sizes obtained using Code sizing techniques should be used consistently for companson to Code acceptance standards whenever possible. | |||
Based on experience, Code sizing techniques appear to be somewhat conservative; however, there is little evidence to support the feasibilityofdeveloping specific tolerances orcorfection factors forCode sizing techniques. Noris there signiiicant evidence ofimproved accuracy and consistency resulting from the use of any one alternate sizing technique. | |||
Alternate sizing methods must be used carefully and, in effect, should be used only when it can File RG1.150 Page 18 | |||
SECOND INSPECTION INTERVAL | SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGULATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1994 be determined that the Code sizing techniques are, forsome reason, inappropriate for the specific type offlaw encounten:d. | ||
These statements do point out that flaw sizes based on UT are estima'tes. FPL, | These statements do point out that flaw sizes based on UT are estima'tes. FPL, ofcourse, has vaporing degrees ofconfidence in flawsize estimates depending on pertinent examination variables. Since the ramificafions ofour flaw'size estimates are very great, FPL willtypicallyrecommend certain actions fo our vendors which can increase our confidencein flawsize estimation. These recommendations may include actions such as: | ||
(a) | (a) placing additional holes in the calibration block (b) | ||
In reference to Paragraph 7.b, procedure qualifications are required and the documentationis reviewed | 'constructing mockups of fhe examination an:a (c) using other NDE equipment (d) applying alternate NDE methods (e) perl'orming certain laboratory tests (fl calling in specialists with particular experience in. similar problems. | ||
Documentationis available | In reference to Paragraph 7.b, procedure qualifications are required and the documentationis reviewed byFPL priorto perl'ormance ofthe examination activity. | ||
In reference to Paragraph 7'.c, FPL requires a detailed limitations report for all reactor vessel examinations. The report is usually a combination of tables and sketches that quantify the various limitations fo the Code required volume. | Documentationis available forreview byfhe enforcement and regulatory authority, and the authorized inspection agency at any time. | ||
The information | In reference to Paragraph 7'.c, FPL requires a detailed limitations report for all reactor vessel examinations. | ||
The report is usually a combination of tables and sketches that quantify the various limitations fo the Code required volume. | |||
The information identifiedin Paragraph 7'.dis required by FPL to beincluded in a final report of the examination activity. | |||
In reference to Paragraph T.e, when alternate techniques are utilized, either for examination or sizing purposes, a complete description of the application and results is included within the final report. | In reference to Paragraph T.e, when alternate techniques are utilized, either for examination or sizing purposes, a complete description of the application and results is included within the final report. | ||
File RG1.150 | File RG1.150 Page 19 | ||
NUCLEAR EKQINEERINQ CSIWODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA | t NUCLEAR EKQINEERINQ CSIWODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) ~181 | ||
'T. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINArlON PSL4004C)A444 Revision 0 Sepiembor 28, 1884 ATTACHMENTB PERCENT OF EXAMINATIONCOVERAGE Examlnathn Area Identlficathn Lower Head-to-- | |||
Lower Shell Circ. | |||
Weld No. 201-141 Beam Angle 0 IAM 45 60 50/704 0 WRV 4A'PT 50/7lPT Beam DIrectIon UP/DN UP/DN UP/DN CWICCW CWICCW CWICCW Percent Coverage 93% | |||
Lower Shell-to- | 10m86% | ||
100/88% | |||
45'T | 100/84% | ||
50/70'T | 93% | ||
93% | |||
93% | |||
93% | |||
FIgure No. | |||
Descripthn of Examlnathn Coverage and umltathns Examination of IWB-25004 E F~ volume limited along length ofweld below core barrel anfntation lugs. | |||
Claimed coverage Is 93% | |||
overall Lower Shell-to-Intermediate Shell Circ. Weld No. 101-171 0 LAM 45'0'0/70''RV 45'T 60'T 50/70'T UP/DN UP/DN UP/DN CWICCW CWICCW CWICCW 92% | |||
92% | |||
92% | |||
92% | |||
85% | |||
85% | |||
85% | |||
83% | |||
Examination of IWB-2500-2 A-BC-D volume limited along length ofweld near vessel material specimen tubes. | |||
Claimed coverage is 88% | |||
overall Upper Shell-to-Middle Shell Circ. | |||
Weld No. 106-121 Intermediate Shell Long. Weld e15 Deg. | |||
No. 101-124A RAM 45 60 50/70 NNRV 4A'PT 50/70 O'am 45'0'0/70''RV 45'T 60'T 50/70'T UP/DN UP/DN UP/DN CW/CCW CW/CCW CWICCW CWICCW CWICCW CWICCW UP/DN UP/DN UP/DN 100ok 100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100ok 100% | |||
100ok None None None None None None None None None None None None None None None None IWB-2500-1 A44-D-volume examined for 100% weld length without limitation. | |||
Claimed coverage is 100% | |||
overall Examination of IWB-2500-2 A-B~ examined for 100% | |||
weld length without limitation. | |||
Claimed coverage is 100% | |||
overall File LISNRCAOA Page 12 | |||
tk | tk | ||
~ | |||
r ~ | |||
'SI NUCLEAR ENQINEERINQ CSIODE PROGRAMS P,.O. BOX 14000 JUNO BEACH, FLA 33408 (407) B$44181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORRATION OF ALTERNATIVE EXAMINATION PSL400~A44 1 Revtohn 0 | |||
No. 101-124B oo Lam 45'0'N70' CWICCW CWICCW GW/CCW 100% | September 28, 1884 Examlnathn Aiba Identlflcathn Intermediate Shell Long. Weld @135 Deg. | ||
No. 101-124B Intermediate Shell Long. Weld 255 Deg. | |||
No. 101-124C Upper Shell Longitudinal Weld O15 Deg. | |||
No. 101-122A Upper Shell Longitudinal Weld O135 Deg. | |||
No. 101-122B Upper Shell Longitudinal Weld O255 Deg. | |||
No. 101-122C Beam Angle oo Lam 45'0'N70' WRV 45'T 60'T 50/70'T 0 Lam 45'0'0/70 O'RV 45'T 60'T 5N70'T 0 Lam 45'0'0nO''RV 45'T 60'T 50/70'T 0 Lam 45'0'0/70''RV 45'T 60'T 50/70'T O'am 45'0'0nO''RV 45'T 60'T 50/70'T Beam Dlrecthn CWICCW CWICCW GW/CCW UP/DN UP/DN UP/DN GWICCW GWICGW CWICCW UP/DN UP/DN UP/DN CWICCW CWICCW CWICGW UPIDN UP/DN UPIDN CWICCW CWICCW CW/CCW UP/DN UP/DN UP/DN CW/CCW GWICCW CWICCW UP/DN UP/DN UP/DN Percent Coverage 100% | |||
100% | |||
100% | |||
100% | |||
100% | 100% | ||
100% | 100% | ||
100% | 100% | ||
100% | |||
74% | |||
100%/70% | |||
100%/55% | |||
100%/74% | |||
100% | |||
100% | |||
100% | |||
100% | |||
95% | |||
98 | 100%/96% | ||
100%N6% | |||
100%99% | |||
97% | |||
79% | |||
74% | |||
95% | |||
96% | |||
100%/98% | |||
100%/98% | |||
100% | |||
98% | |||
87% | |||
83% | |||
97% | |||
96% | |||
100%NB% | 100%NB% | ||
100%98% | 100%98% | ||
100% | 100% | ||
98% | |||
Examination of IWB-2500-2 A-volume was limited at | 87% | ||
83% | |||
97% | |||
Figum NO. | |||
File USNRCAOA | None None None None None None None None 185 DescrIpthn of Examlnathn Coverage and Umltathns Examination of IWB-2500-2 A | ||
~ examined for 100% | |||
weld length without limitation. | |||
Claimed coverage Is 100% | |||
overall Examination of IWB-2500-2 A-B~D volume limited from one side along length ofweld near vessel material specimen tubes. Claimed coverage is 87% overall Examination of IWB-2500-2 A-B~ volume was limited at Intersection with the adjacent outlet nozzle integral extension. Claimed coverage Is 92% overall Examination of IWB-2500-2 A-BN-D volume was limited at lnterseclion with the adjacent inlet nozzle inner blend. | |||
Claimed coverage is 94% | |||
overall Examination of IWB-2500-2 A- | |||
~ volume was limited at intersection with the adjacent inlet nozzle Inner blend. | |||
Claimed coverage is 94% | |||
overall File USNRCAOA Page 13 | |||
r | r | ||
~ | |||
Ilgwu 1SI NUCLEAR ENQINEERINQ CSINODE PROQRAMS P,O. BOX 14000 JUNO BEACH, FLA 88408 (407) 8944181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400447A44 1 | |||
Revision 0 SePtimber 28, 1994 Examlnatlon Area identification Beam | |||
101-142A 0 LAM I | 'eam Angle Direction Percent Coverage Figure NO. | ||
Descrfptlon of Examination Coverage and Umhttlons Lower Shell Longitudinal Weld O15 Deg. No. | |||
101-142A Lower Shell Longitudinal Weld | |||
@135 Deg. No. | |||
101-142B Lower Shell Longitudinal Weld 225 Deg. No. | |||
101-142C 0 LAM 45I 50/70 0 WRV 4W QFT 50/70'r 0 LAM 45 80 50/70 0 WRV 4W QPT 50/7O'r 0 I%M 45I 50/70'NRV 4W SPT 50/70T CWICCW CWICCW CWICCW UP/DN UP/DN UP/DN CWICCW CWICCW CWICGW UP/DN UP/DN UP/DN GWICCW CWICGW CW/CCW UP/DN UP/DN UP/DN 100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | 100% | ||
100% | 100% | ||
100% | 100% | ||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
100% | |||
87% | |||
100%/85% | |||
100%/77% | 100%/77% | ||
100%/87% | 100%/87% | ||
BN volume limited from one side along length of weld near reactor vessel material | 100% | ||
100% | |||
File USNRCAOA | 100% | ||
100% | |||
None None None None None None None None None None None None None None None None Examination of IWB-2500-2 A- | |||
~ examined for 100% | |||
weld length without limitation Examination of IWB-2500-2 A-BC-D examined for 100% | |||
weld length without limitation Examination of IWB-2500-2 A-BN volume limited from one side along length of weld near reactor vessel material sPecimen tubes. Claimed coverage Is 93% overall File USNRCAOA Page 14 | |||
s +,) | |||
~ | ~ | ||
l | |||
~ | |||
~. | |||
ISI | CP ISI t | ||
NUCLEAR ENQINEERINQ CSI&ODE PROGRAMS PO. BOX 14000 JUNO BEACH, FLA 88408 (407) 68~181 RRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400 JC)A4I4-1 RevteIen 0 | |||
September 28, 1884 ATTACHMENTC EXAMINATIONLIMITATION DRAWINGS File USNRCA,OA Page 15 | |||
2-LEAK MONITOR TUBES | 2-LEAK MONITOR TUBES 172-103A e 16s. | ||
172-103B e | 172-103B e | ||
345'UTLET NOZZLE INNER RADIUS AREA ON-IR-A e O'OCATIO QN-IR-B e | |||
103-151- | 180 LOCATI 101-122-A 101-122-B 101-122-C INLET NOZZLE INNER RADIUS AREA IN-IR-A e 60 LocATION IN-IR-B e 120'OCATION IN-IR-C e 240'OCATION IN-IR-D e 300'OCATION 103-151-A e 10'OCATION 103-1$ 1-B e 40'OCATION 101-124-A 101-124-B 106-121 101-171 2998-4395 REV. | ||
1 E-71172-171-002 REV. 0 E-71172-171-008 REV. 0 103-1$ 1-C e 8s LocATION 103-151-D e 135'OCATION 103-151-E e 160'OCATION 103-151-F e 205'OCATION 103-151-G e 250'OCATION 103-151-H e 280'OCATION 103-151-I e 325'OCATIO CORE STOP LUG 101-122-C 101-142-A 101-142-B I | |||
REV, | 101-142-C t | ||
FLOV BAFFL FB-01 201-141 CORE STABILIZING LUG (SNUBBER) 101-141-A e O'OCATION 101-141-B e | |||
60 LocATION 101-141-C e 120'ocATIQN 101-141-D e 180'OCATION 101-141-E e 240'OCATION 101-141-F e 300'OCATION | |||
~i SECTION A-A-SEE DMG. 02-001-B SECTION B-B-SEE DMG. 02-001"B SECTION X-X-SEE DVG. 02-001-C SECTION Y"Y-SEE DVG. 02-001-C SECTION Z-Z-SEE DVG. 02-001-C REFERENCE DRAVINGS E-71172-121-001 REV. 4 E-71172-124-001 REV. 5 E-71172-141-001 REV. 2 E-71172-141-002 REV. 6 E-71172-142-001 REV. 7 E-71172-151-001 REV. 5 E-71172-154-001 REV, 4 NOTES CALIBRATION BLOCKS AND HATERIAL 2-LEAK HONITOR TUBES AND FITTINGS <SB-166) | |||
UT-I, UT-2. UT-10 DATE< 9/28/94 ELA ZONEi I DRA VII'b ISI SKETCH 02 001 REVl$104 2 | |||
FLORIDA PQVER L LIGHT ST. LUCIE UNIT 2 TITLEiREACTOR PRESSURE VESSEL | |||
0'5'I I | 0'5' I | ||
60'0' I | I 60'0' I | ||
120'35'I I | 120'35'I I | ||
180'40'55'70' | 180'40'55'70' 101-121 300'60' AREA OF ID TAPER NOZZLE INTERFERENCE WITH VERTICAL WELD TRANSVERSE SCANS 101-122A | ||
~ 101-1228 | |||
~ 106-121 ~ 101-122C RPV MATERIAL SPECIMEN TUBES 101-124A | |||
180'40'77'84'63 | ~ 101-1248 101-124C 33'53'3 | ||
~ 101-171 00 101-142A 60'20'3'7'04' 101-1428 O | |||
180'40'77'84'63~ 101-142C 300'60'LOW SKIRT SUPPOR CORE BARREL ANTI ROTATION LUG 10'0'01-154A 40'5 90'01-1548 130 150 101-154C 160'05'10'01-154D 250 270'01-154E 280'25'30'01-154F FLOW SKIRT UPPER EDGE FLOW SKIRT LOWER EDGE ROLL OUT INSIDE VIEW INACCESSIBLE SCANNING SURFACES 101-151 FIGURE 1.1 REACTOR PRESSURE VESSEL ROLL OUT VIEW | |||
RPV MATERIAL SPECIMEN INTERMEDIATE AND LOWER SHELL VERllCAL WELOS AT 255'ESSEL | RPV MATERIAL SPECIMEN INTERMEDIATE AND LOWER SHELL VERllCAL WELOS AT 255'ESSEL AZIMUTH PARALLEL EXAMINATION UMITATION (0,'5, 60, 50/70'CW BEAMS) | ||
FIGURE 1.5 | FIGURE 1.5 VERTICAL WELD UMITAllONS | ||
na | na os | ||
CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA | ~ | ||
1SI t | |||
NUCLEAR ENGINEERING CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 53408 (407) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PS L4004OA4I4-1 Revkbn 0 | |||
SepIember 28, 1884 END OF DOCUMENT Fite USNRCAOA Page 16 | |||
~ | |||
4 y 4 | |||
~8 I | ~8 I | ||
4" | 4" Vr | ||
+PI | |||
~r I.}} | |||
Latest revision as of 13:42, 8 January 2025
| ML17228A881 | |
| Person / Time | |
|---|---|
| Site: | Saint Lucie |
| Issue date: | 09/28/1994 |
| From: | FLORIDA POWER & LIGHT CO. |
| To: | |
| Shared Package | |
| ML17228A880 | List: |
| References | |
| RTR-REGGD-01.150, RTR-REGGD-1.150 PSL-200-AOA-94, NUDOCS 9410200233 | |
| Download: ML17228A881 (41) | |
Text
FLORIDA POWER AND LIGHTCOMPANY NUCLEAR ENGINEERING DEPARTMENT P.O. Box 14000 Juno Beach, Florida 33408 ST. LUCIE NUCLEAR PlANT, UNIT 2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATIONOF ALTERNATIVEEXAMINATION Prepared by Component, Support and Inspection Department Code Programs Group For St LucIe NucIear Power PIant 6501 South Hwy. A1A Jensen
- Beach, Florida 34957 Commercial Service Date:
USNRC Docket Number.
Document Number.
Revtsion Number.
0 Date:
August 8, 1983 50-389 PS L-200-AOA-94-1 September 28, 1994 4410200233 4l410iZ PDR ADQCK 05000389 9
=
..PDR
ISI NUCLEAR ENGINEERING Csl&ODE PROGRAMS P,.O. BOX 14000 JUNO BEACH, FLA 33408 (40'> eem181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL4004LDA4I4-1 Revhbn 0
Sephmbor 28, 1884 ABSTRACT Florida Power and Ught Company (FPL) has determined, based upon the results of previous examination documentation, that we are unable to completely satisfy the requirements for augmented reactor vessel shell weld examinations specified in 10 CFR 50.55a(g)(6)(il)(A) of the Code of Federal Regulations.
This submittal provides the information to justify FPLs determination, supplemented by documentation required by the Commission to grant FPL's Request for Alternative Examinations for satisfying the St. Lucie Nuclear Power Plant, Unit 2, Augmented Reactor Vessel Shell Weld
'xamination.
The requirements forthe augmented examination ofthe reactor vessel shell welds was conducted, during the First Inservice Inspection Interval, which began on August 8, 1983 and ended on August 8, 1993.
The First Inservice Inspection (ISI) Program was developed based on the rules set forth in the ASME Boiler and Pressure Vessel Code,Section XI 1980 Edition through the Winter 1980 Addenda.
File USNRCA,OA Page 2
ISI NUCLEAR ENGINEERING OS!MODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA S$408 (407) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4 1 Revtabn 0
September 28, 1884 1.0 SCOPE FPL has made a determination that we are unable to completely. satisfy the requirements for augmented reactor vessel shell weld examinations specified in Title 10; Code of Federal Regulations, Part 50, Section 55a(g)(6)(ii)(A).
This document as required by 10 CFR 50.55a(g)(ii)(A)(5), provides the information to support the determination and the proposed alternatives to the examination requirements that provide an acceptable level of quality and safety.
2.0 EXAMINATIONREQUIREMENTS FPL shall augment our reactor vessel examination by implementing once, as part of the inservice inspection interval in effect on September 8, 1992, the examination requirements for reactor vessel shell welds specified in Item B1.10 of Examination Category B-A, "Pressure Retaining Welds in Reactor Vessel, " in Table WB-2500-1 of subsection IWB of the 1989 Edition of Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code, subject to the conditions specified in 10 CFR 50.55a(g)(ii)(A)(3) and (4).
FPL has elected not to defer the augmented examinations in accordance with 10 CFR 50.55a(g)(ii)(A)(3),
and therefore the augmented examinations were performed in accordance with the related procedures specified in 1980 Edition through the Winter 1980 Addenda of Section XI, applicable to the St. Lucie Unit2 First Inservice Inspection Interval in effect on September 8, 1992.
Table 2.1 below provides the examination requirements for the augmented reactor vessel shell welds for Examination Category B-A, Item B1.10, Table 2.1 EXAMINATIONCATEGORY B-A PRESSURE RETAINING WELDS IN REACTOR VESSEL Item Parts No.
Examined B1.10 Shell Welds Examination Requirements NIA Examination Method Volumetric Extent and Frequency of Examination AII Welds'1.11 CIrcumferentlal IWB-2500-1 Volumetric B1.12 Longitudinal IWB-2500-2 Volumetrfc Includes essentially 100% of the weld length All Welds'll Welds'ile USNRCAOA Page 3
ISI NUCLEAR ENGINEERING cslwoDE PRoGRAMs P.O. BOX 14000 JUNO BEACH, FLA
,88408 (407) 8844181 ST. WCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAI.
REQUEST FOR AUTHOIUZATION OF ALTERNATIVE EXAMINATION PSL4004ClA4I4-1 Ravtabn 0
SepSember 28, 1884 NOTE:
For the purpose of the augmented examination of the reactor vessel, essentially 100 percent as used in Table IWB-2500-1 means more than 90 percent of the examination volume of each weld, where the reduction In coverage is due to interference by another component, or part g'eometry.
3.0 AUGMENTED EXAMINATION The augmented examination of the reactor vessel is satisfied by an examination of essentially 100 percent of the reactor vessel shell welds specTiied in 10 CFR 50.55a(g)(6)(ii)(A)(2) that has been completed during the inservice inspection interval in effect on September 8, 1992.
FPL is unable to satisfy the augmented reactor vessel shell weld examination requirement to essentially perform 100 percent examination coverage ofthe augmented reactor vessel shell welds specified in 10 CFR 50.55a (g)(6)(ii)(A)(2), because configuration and permanent attachments prohibit essentially 100% ultrasonic examination coverage of the required examination volume.
Described below, coupled with the Tables and Figures, are details of the examination limitations by weld description. The accompanying Figures graphically depict the locations and extent of the limitations with respect to weld metal and associated base material. The Table quantifies the limitations in terms of present code required volume which was effectively covered.
3.1 CIRCUMFERENTIALSHELL WELDS A.
LOWER SHELL TO LOWER HEAD WELD The mechanized examination of the Lower Shell-to-Lower Head weld 201-141 of Figure IWB-2500-3, volume E-F-G-H is limited due to interference from the core support lugs and anti-rotation lugs.
Figure 1.1 is a roll out view showing the inaccessible scan surfaces from the vessel inside surface and shows the volume of material not examinable from the inside surface where scanning was limited by lug interference.
INTERMEDIATESHELL TO LOWER SHELL WELD Examination of the Intermediate Shell-to-Lower Shell weld 101-171 of Figure IWB-2500-2, volume A-B-C-D is limited along the length of the weld due to interference from the material surveillance specimens.
Figure 1.1 is a roll out view of weld 101-171 depicting areas where examination scans can not be performed.
File USNRCAOA Page 4
e L
1
~ E
ISI NUCLEAR ENGINEERING CSIODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 6844181 ST. LIICIEUNIT2 RRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNAllVE EXAMINAlION PSL400~A4I4-1 RevhIon 0 Sap1ambor 28, 1884 C.
UPPER SHELL TO MIDDLESHELL WELD Examination of the Upper Shell-to-Middle Shell weld 106-121, of Figure IWB-2500-1, volume A-~D, volume is effectively examined 100% of the weld length without limitation.
3.2 LONGITUDINALSHELL WELDS A.
LOWER SHELL WELDS The examinations of the Lower Shell Vertical welds 101-142A, B and C of Figure IWB-2500-2, volume A-B-C-D, with the exception of 101-142C were essentially 100% examined for the length of the weld. The examination of weld 101-142C is limited due to interference of the surveillance capsules.
The limitations are shown on Figure 1.1 and 1.5.
B.
MIDDLESHELL WELDS Examinations ofthe Middle Shell Vertical welds Figure IWB-2500-2, volume A-B-C-D, welds 101-124A, and B volume is effectively examined 100% of the weld length without limitation. The examination of the Middle Shell Vertical welds 101-124C, is limited from one side by interference from the material surveillance capsules as shown on Figure 1.1.
C.
UPPER SHELL WELDS Examination of the Upper Shell Vertical welds Figure IWB-2500-2, volume A-B-C-D, welds 101-122A, B, and C is limited by interference from the inlet nozzle inner radius blend and the outlet nozzle integral extension as shown on Figure 1.1.
However, the examinations are complemented by the Nozzle-to-Shell weld examinations.
4.0 DISCUSSION 10 CFR 50.55a (g) (4), recognizes that throughout the service life of a nuclear power facility, components which are classified as ASME Code Class 1 shall meet the requirements, except design and access provisions requirements, set forth in Section XI, to the extent practical within the limitations of design, geometry and materials of construction of the components.
File USNRCAOA Page 5
NUCLEAR ENQINEERINQ CSIODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 8844181 ST. WCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4-1 Rivichn 0 SOPI4rnber 28, 1884 4.1 NEW REGULATION 10 CFR 50.55a(g)(6)(II)(A) CHANGE The change in the regulation has little or no effect on the St. Lucie Nuclear Power Plant, Unit 2, First 10-Year Inservice Inspection Interval schedule examinations, as FPL performs essentially 100% volumetric examination of all reactor pressure vessel weld lengths, to the extent practical each inservice inspection interval.
The last mechanized (automated) examination activity was performed during the 1989 refueling outage, which was part of the first inservice inspection interval In
.effect on September 8, 1992 when the rule change became effective.
Because FPL inservice examinations were extended to Include essentially 100%
of all reactor pressure vessel welds the augmented reactor vessel examination requirements of the rule change which became effective on September 8, 1992, meet the examination requirements for reactor vessel shell welds specified in Examination Item B1.10 of Examination Category B-A, "Pressure Retaining Welds in Reactor Vessel," in Table IWB-2500-1 of Subsection IWB of the 1989 Edition of Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code, and subject to the conditions specified in 10 CFR 50.55a(g)(6)(ii)(A)(3) and (4).
4.2 FIRST INSPECTION INTERVAL During the 1989 refueling outage, of the St. Lucie Nuclear Power Plant, Unit 2, First Inservice Inspection Interval, Southwest Research Institute (SwRI) using their Enhanced Data Acquisition System performed the Reactor Pressure Vessel mechanized (automated) ultrasonic examinations.
These examinations covered the essentially 100% of all Reactor Pressure Vessel shell circumferiental and longitudinal welds, to the extent practical within the design, geometry and materials of construction.
These examinations were conducted to satisfy the requirements of the 1980 Edition through the Winter 1980 Addenda of Section XI. In addition to the 80W80 Code requirements, the mechanized examination activity was extended to include all Reactor Pressure Vessel accessible weld lengths.
NOTE: i It is the intent of FPL to use the First Inservice Inspection interval examinations to satisfy the augmented examination requirements of the rule change.
4.3 NDE EXAMINATIONPROCEDURES NDE examination procedures implemented during the St. Lucie Unit 2 Reactor Pressure Vessel examinations utilized the 1980 Edition through the Winter 1980 ASME Section XI Code-specified ultrasonic techniques.
These techniques were File USNRCA,OA Page 6
NUCLEAR ENQINEERINQ CSINODg PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA
$8408 (401) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL RECIUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL4004C)A84 1
Revtebn 0
SepRmber 28, 1884 augmented by special SwRI qualified examination techniques to obtain full coverage of the near surface and underclad material volumes.
4.4 EXAMINATIONCOVERAGE All of the RPV welds were examined for 100% of accessible weld lengths, The flowskirt, core barrel lugs, and material specimen tubes limited fulllength scanning access to some welds. The outlet nozzle integral extensions and fiange-to-skell weld joint configuration limited fullcoverage of some weld volumes by all ultrasonic
,examination techniques.
A fullvee path calibration of the 45'hear wave scan was used to compensate for limitations encountered in the near surface and those due to geometric shadowing.
A 50/70'i-modal ultrasonic examination was used for examination of the Inner 25 percent t.
Examination limitations were reported in detail as required by USNRC Regulatory Guide 1.150, Revision 1. Weld examinations where 90% or greater coverage of the volume was achieved are considered as having met essentially 100%
requirement as used in Table IWB-2500-1 of the ASME Code.
Examination limitations which received less that 90% coverage, as required by Code Case N-460 were documented in the form of a Request for Relief and submitted as part of the 'St. Lucie Unit 2 Second Inservice Inspection Interval Update Program Submittal.
NOTE:
It should be noted that electronic gating does not result in any examination limitations since the entire instrument screen presentation is monitored during the examinations, video taped, and reviewed independently following the examinations.
Attachment B provides Tables of all augmented examination percent of coverage for those welds which fall within the augmented examination requirements of the regulation. The peIcent of coverage Included in Attachment B provides the coverage for all applicable welds, whether or not the coverage achieved was greater or less than 90% as stated in Code Case N-460.
4.5 CODE CASE NQ60 Code coverage requirements, as allowed by Code Case NQ60 is implemented by FPL on vessels as follows:
File USNRCAOA Page 7
ISI NUCLEAR ENQINEERINQ CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 8844181 ST. LUCIE UNrr 2 RRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION Of ALTERNATiVE EXAMINATION PSL400~A84 1
Revkbn 0 Sepiember 28, 1884 The 0'amination scan is intended to be utilized once to Identity conditions which may interfere with the examination of the weld and the required volume (1/2t). Coverage with this search unit is not factored into the overall calculation of weld coverage.
2.
The required examination angles are 0', 45'/2 vee path, and 60'/2 vee path. Of these, the two angle beams applied in two directions parallel with the weld and in two directions perpendicular to the weld are factored into the calculation. Except in cases where the beam is oriented essentially perpendicular to the plane of postulated flaws, the 0'xamination contributes nothing to the examinations, therefore, it is not factored Into the calculation.
3.
FPL elected to add enhancements to the overall examination of the reactor pressure vessel, as follows:
a.
A full vee path 45'o enhance the examination of the area directly under the cladding and to reduce areas of non coverage due to scan limitations.
b.
A special bi-modal scan of the cladding-base metal interface and 1/4 t under the cladding. This was not factored into the coverage calculations, except to augment weld examinations where clad roughness exhibited near. surface noise.
4.
The overall coverage calculation consists of an average of the 45'nd 60'xaminations in all four directions.
4.6 USNRC REGULATORY GUIDE 1.150 Regulatory Guide 1.150, Ultrasonic Testing of Reactor Vessel Welds During Preservice and Inservice Examinations was also used during the examination activity.
FPL was one of the first utilities to implement the regulatory guide when itwas still in the draft mode. FPL along with its vendor, SwRI held several meetings with the USNRC prior to implementation. The last St. Lucie mechanized Reactor Pressure Vessel Examination activity was conducted during the 1989 refueling outage, and FPL implemented Regulatory Guide 1.150, Rev. 1. Appendix A, provides FPL's position for compliance with Regulatory Guide 1.150.
File USNRCAOA Page 8
NUCLEAR ENQINEERINQ CSINODE PROQRAMS P.O. BOX 14000 JUNO BEACH, FLA
$8408 (407) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4-1 Recon 0
Seplamber 28, 1884 4.7 OTHER CONSIDERATIONS As required by IWB-2200, FPL determined prior to the performance of the preservice examinations that the examination of the reactor pressure vessel will be conducted from the inside surface ofthe vessel, utilizing mechanized ultrasonic equipment and with techniques equivalent to those that are expected to be employed for subsequent inservice examinations. This decision was made based on the following criteria:
1.
access for the inspector, examination personnel and equipment necessaly to conduct the examinations; 2.
Sufficient space for removal and storage of structural members (vessel internalS, shielding and insulation; 3.
installation and support of handling equipment (e.g., hoists) to facilitate removal, disassembly and storage of equipment.
Because of the limited access between the vessel and bioshield wall, conducting the examinations from the external surface for the purpose of investigating the small amount of weld volume missed during the mechanized inside surface examinations would require the desttuction of the insulation during the removal
- process, excessive
- manhours, manrem, and substantial costs without providing any substantial increase in the quality and safety of the unit.
5.0 ALTERNATIVEEXAMINATIONSOR TESTS:
The extent of examination volume achieved ultrasonically and the alternate scans performed (see Examination Coverage Table Attachment B) coupled with the system pressure tests provide assurance of an acceptable level of quality and safety. As an alternative FPL performed the following:
1)
Periodic System Pressure tests per Category B-P, Table IWB-2500-1 2)
Conduct essentially 100% Mechanized (automated) Ultrasonic Examinations to the extent practical on all reactor pressure vessel welds from the inside surface.
3) 50/70'i-modal ultrasonic examination of the inner 25 percent t.
4)
Conduct a full vee 45'hear wave examination to the extent practical to compensate for recorded limitations.
5)
Employ as they become available additional examinations, inspections and/or techniques that would provide a substantial increase in the examination of areas File USNRCA,OA Page 9
ISI NUCLEAR ENGINEERINQ CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 33408 (407) 6844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZAlloN OF ALTERNATIVE EXAuINATION PSL400~A4I4-1 Ravlabn 0 SepIember 28, 1884 currently missed under current examination techniques.
6.0 IMPLEMENTATIONSCHEDULE
First Inservice Inspection Interval - August 08, 1983 to August 07, 1993 7.0 ATTACHMENTSTO THE SUBMITTAL Attachment A Implementation of Regulatory Guide 1.150 Attachment B Percent of Coverage Tables Attachment C Examination Umitation Drawings.
File USNRGA,OA Page 10
NUCLEAR ENQINEERINQ CSIODE PROQRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) 6844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400~A4I4 1 Reviake 0
Se PIember 28, 1884 ATTACHMENTA IMPLEMENTATIONOF REGULATORY GUIDE 1.150 File USNRCAOA Page 11
NUCLEAR ENGlNEERING DEPARTMENT COMPONENT, SUPPORT AND INSPECTIONS DEPARTMENT P.O. Box 14000 JUNO BEACH, FLORIDA 33408 St. Lucle Nuclear Power Plant Unit 2 SECOND INSERVICE INSPECTION INTERVAL SECOND INSPECTION PERIOD IMPLEMENTATIONOF REGULATORY GUIDE 1.150 Prepared by Florida Power and Ught Company Code Programs Group For St. Lucie Nuclear Power Plant 10 Miles South of Ft. Pierce on A1A Ft. Pierce, Florida 33034 Commercial Service Date:
NRC Docket Number:
Document Number.
Revision Number.
August 8, 1983 50-389 PSL-RG 1.150 0
Date: September 28, 1994
SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 ABSTRACT This document provides a summary of how Florida Power and Light Company (FPL),
implements fhe tequirements ofRegulafoty Guide 1. 150. FPL has complied, to the extent practical with the requirements of this regulatory guide for over 10 years. FPL, and our vendor Southwest Research Institute (SwRi), has conducted examinations on the reactor pressure vessels at bofh sifes (Sf. Lucie and Turkey Point), and on all four units (PSL-1 and 2, PTN 3 and 4).
Where required in fhis document SwRi isinserted, in place ofFPL, fo make a disfincfion between equipment, techniques, or documentafion unique to SwRI.
The mechanized ultrasonic examinations for the St. Lucie Nuclear Power Plant, Unit 2, Reactor Pressure Vesselis cunenfly scheduled fo be performedin fhe Second Inspection Period, of the Second Inspection Interval. The examinations will be conducted in accordance with the Amencan Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI, 1989 Edition, no Addenda, and fhe additional requirements of Regulatory Guide 1. 150 as stated within.
This documentis writtenin a format fhat firsidentifie the regulatory guide requitement, followed by a summary ofhow FPL willimplement that requitement.
File RG1.150 Page 2
SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 INTRODUCTION Ultrasonic examination of the St. Lucie, Unit 2 reactor pressure vessel welds, Including the closure head will be performed during the upcoming Second Inservice Inspection Interval, in accordance with the 1989 Edition of the American Society of Mechanical Engineers (ASME), Boiler and Pressure Vessel Code (B&PVC),Section XI, and as supplemented by the additional requirements of Regulatory Guide 1.150, Revision 1. This document summarizes the additional requirements that Florida Power and LightCompany (FPL) implemented during previous examination activities in order to comply with the Regulatory Guide requirements.
FPL expects that these additional requirements willnot change.
1.0 INSPECTION SYSTEM PERFORMANCE CHECKS The conduct of nondestructive examinations require that the performance characteristics of the Inspection system used be well defined and documented.
This is particularly true for situations which require comparisons of examination results generated during successive examinations on the same components. An inspection system comprises of the following:
a.
a transducer (search unit);
b.
a single-channel instrument or each channel of a multichannel instrument; and c.
a given cable type and length.
The checks described in paragraphs 1.1 and 1.2 should be made forany ultrasonic (UT) system used for inspection of reactor pressure vessel (RPV) welds.
The field performance checks described in 1.2 (with the possible exception of 1.2.c) should be conducted on a basic calibration block that represents the thickness range to be examined.
FPL agrees with the need to define and document the performance characteristics ofUT systems, and we have been, and requiring our vendors (SwRl) to do so formany years.
Most of the checks identliied herein are considered standard operating practice. FPL applies these requirements to all reactor vessel weld examinations, whether the examinations are manual, orautomated (Mechanized) from the inside surface. Since the results of the field performance checks described in 1.2 are independent of calibration block design, FPL approved vendor's procedures are required to allow the use of any calibration block that willprovide the signal responses needed forthe performance check.
File RG1.150 Page 3
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 Preexamina5on Performance Checks a.
Frequency of Checks These checks should be verified within six (6)'months before reactor pressure vessel examinations performed during one outage. Pulse shape and noise suppression controls should remain at the same settings during calibration and, examination.
b.
RF Waveform Arecord ofthe RF (radiofrequency) pulse waveform from a reference reflector should be obtained for each search unit used in the examination in a manner which will provide frequency amplitude information. At the highest amplitude portion of the beam, the RF return signal should be recorded before it has been rectified or conditioned for display. The reflector used in generating the RF return signal as well as the electronic system (i.e., the basic ultrasonic instrument, gating, and form of gated signal) should be documented.
These records should be used for comparison with previous and future records.
FPL requires vendors not only to record RF pulse waveform asidentified above, but also requires the determination of the frequency spectrum and distance amplitude curve for each search unit used. Search units that do not meet strict performance tolerances are prohibited from use. Documentation ofthis analysis is submitted to FPL priorto the performance ofthe examinations and are included as part of the final report of the examination activity.
In addition to the analysis described above, FPL also requires photographs ofthe RF waveformin the field during initiaand finalcalibrations. This provides a record ofthe RF waveform obtained using the specific system components (transducer, instrument, and cable) that are used for calibration and examination.
1.2 Field Performance Checks a.
Frequency of Checks As a minimum, these checks should be verified on site before and after examining all the welds that need to be examined in a reactor pressure vessel during one outage.
Pulse shape and noise suppression controls should remain at the same settings during examination and calibration.
File RG1.150 Page 4
SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1884 Instrument Sensitivity During Llnearlty Checks The initial instrument sensitivity during the performance of 1.2,e should be such that it falls at the calibration sensitivity or at some point between the calibration sensitivity and the scanning sensitivity.
RF Waveform Arecord ofthe RF (radiofrequency) pulse waveform from a reference reflector should be obtained and recorded in a manner that will permit extraction of frequency amplitude information. At the highest amplitude portion of the beam, the RF return signal should be recorded before it has been rectified or conditioned for display.. This should be determined on the same reflector as that used in 1.1.b above. This record should be retained for future reference.
d.
Screen Height LInearity Screen height linearity of the ultrasonic instrument should be determined according to the mandatory Appendix I to Article 4,Section V of the ASME'ode or Appendix I to Section XI of the ASME Code.
e.
Amplitude Control Unearlty Amplitude control linearity should be determined according to the mandatory Appendix II ofArticle 4,Section V, of the ASME Code or Appendix I of Section XI of the ASME Code.
Angle Beam Prone Charactertzatlon The vertical beam proflile should be determined for each search unit used during the examination by a procedure similar to that outlined in nonmandatory Appendix B-60, Article 4,Section V, of the ASME Code or Appendix I to Section XI of the ASME Code. Beam profile curves should be determined at different depths to cover the thicknesses of materials to be examined. Interpolation may be used to obtain beam profile correction for assessing flaws at intermediate depths for which beam profile has not been determined.
Beam profile measurements should be made at the sensitivity required for sizing. For example, sizing to 20-percent DAC criteria requires that the beam profile be determined at 20-percent DAC.
File RG1.150 Page 5
il SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 The field performance checks described above are performed as follows:
(1)
RF Wavef'ann - Photographs ofthe RF waveformin the field during each initial and final calibration. This provides a record of fhe RF waveform obfained using the specific system components (transducer, instrument, and cable) that are used forcalibration and examination.
(2)
Scraen height Lineanfy - Screen height linearity checks are performed for each instrument in accordance with the Regulatory Guiderequirements. Thesechecksare performedimmediafelybefore and after complefion ofthe examinations.
p)
Amplitude Control Linearity - Amplitude control linearity checks establish a linear relationship befween an adjusfment ofthe gain, or sensitivity, controls (knobs orswitches) and the conssponding signal amplitude change observed on the CRT.
In the case ofmanual examinations in accordance with Regulatory Guide 1.150, amplifude control linearity is determined for each instrument in accordance with the Regulatory Guide requirements.
These checks are performedin conjunction wifhthe screen height lineanfy checksimmediately before and after completion offhe examinafions.
Paragraph 1.2.b above requires that the instrument sensitivity during the performance of amplitude control linearify checks should be af the calibrafion sensitivity or scanning sensitivity. However, the calibrafion sensitivity levels (and scanning sensitivity levels) vary with the different techniques used during vessel examinations.
Therefore, vendors are required fo perform these linearity checks at the extreme upper and lower ends of fhe sensitivity range.
This ensures fhat fhe instrument is linear across a wide range of calibrafion and screening sensitivify levels.
In fhe case ofautomated examinafions, Gain Control circuity electronically compensafes forthe normal signal affenuatI'on that causes a sloping DAC curve and provides a variable gain adjustment across the CRT screen such that a consfant, horizontal DACcurveis attained. Gain Control performance is periodically verified on site during examinafions to assure that a straight horizontal DACis maintained. In essence, whenever the amplitude controls are used forindication amplitude measurements, amplitude confrollinearity checks are performed.
File RG1.150 Page 6
I SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28. 1994 (4)
Angle-Beam Profile Characfenzation-Abeam profile foreach single element pulse-echo angle beam search unitis determined on sifein accordance with the Regulatory Guide requirements.
These profiles are generated using the 1/4, M', and 3/4T side-drilled holes in a calibration block that is as thick or thicker than the component to which the search unit will be applied.
Since Appendix A of the Regulatory Guide permits sizing at either 2096 or 5096 of DAC, Vendors are required to take both 2096 and 5096 beam profiles.
With the use of tandem dual-refracted longifudinal wave units for near surface examination, typical sizing methodologies are not applicable because of the unique search unit performance.
Therefore, when near surface indications are observed with these techniques, special supplemental sizing techniques may be required depending upon the observed characteristi of fhe flaw These special supplemental sizing techniques have been substantiated and qualified using mockups, fieldexpenence, and research project data over many years.
2.0 CAUBRATION System calibration should be performed to establish the DAC curve and the sweep range calibration in accordance with Article 4,Section V, of the ASME Code or Appendix I to Section XI. Calibration should be confirmed before and after each RPV examination, or each week in which the system is in use, whichever is less.
Where
- possible, the same calibration block should be used for successive inservice examinations of the RPV.
FPL requires system calibration be performed on site in accordance with Regulatory Guide requirements on fhe applicable basic calibration block.
Calibration confirmation during manual examinations is performed prior to the examination; af least every four hours dunng fhe examinations; with any substitution of search unit, cable, or power source; and upon completion of the examinations.
For mechanized examinations, FPL requires calibration confirmation prior to the start of a series of examinations (a series is considered to be similar examinations performed using the same examinafion techniques and the same equipment configuration); with any substitution ofsearch unif, cable, orpower source; whenever the device is removed from the examination area; at leasf every week durin the examinafions; and at fhe completion of a series of examinafions.
File RG1.150 Page 7
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 NOTE:
While this calibration confirmation frequency is consistent with the Regulatory Guide, itsometimes does not comply withthe 12-hour frequency requirements of paragraph T-432.1.2 of Section V. The acceptability of exceeding the Section V 12-hour calibration check can be demonstrated as allowed in paragraph IWA-2240 of Section XI.
2.1 Calibration for Manual Scanning For manual sizing of flaws, static calibration may be used if sizing Is performed using a static transducer.
When signals are maximized during calibration, they should also be maximized during sizing. For manual scanning for the detection of flaws, reference hole detection should be shown at scanning speed and detection level set accordingly.
As required above, vendors are requin:d to use static calibration and static sizing techniques formanual examinations, maximizing both calibration and flawsignals.
Reference hole detection is verified by scanning over the calibration block at the maximum scanning speed and verifying that the signal meets or exceeds the recording level.
2.2 Calibra5on for Mechanized Scanning When flaw detection is to be done by mechanized equipment, the calibration should be performed using the following guidelines:
a.
The DAC curve should be established using either a moving transducer mounted on the mechanism that will be used for examination of the component or a mechanism that duplicates the critical factors (e.g.,
transducer mounting, weight, pivot points, couplant) present in the scanning mechanism.
b.
Calibration speed should be at or higher than the scanning speed, except when correction factors established in 2.2.d are used.
C.
The direction of transducer movement (forward or backward) during calibration to establish the DAC curve should be the same direction during scanning unless it can be shown that a change in scanning direction does not reduce flaw detection capability.
One of the following alternative guidelines should be=followed to establish correction factors if static basic calibration is used:
(1)
Correction factors between dynamic and static response should be established using the basic calibration block or, File RG1.150 Page 8
SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 (2)
Correction factors should be established using models and taking scaling factors into consideration (assumed scaling relationship should be verified) or, (3)
Correction factors should be established using full-scale mockups.
FPL complies with these requiremenfs forcalibration formechanized scanning in accordance wifh2.2.d(1) in that we have repeatedly required SeRI to demonstrate equivalency between the scanning with fhe PaR devices and fhe sfafic calibration techniques.
FPL also requires SwRi to provide a report documenting this equivalency using the equipment perfl'nent to FPL's application.
2.3 Callbra5on Confirmation Calibration confirmation performed as midshift or interim confirmation between onsite calibrations should comply with stability requirements in T-433, Article 4,Section V, of the ASME Code.
When an electronic simulator is used foronsite calibration confirmation after a Code required block calibration performed off site, the following should also apply:
a.
Complete system performance should be maintained stable prior to offsite calibrations and onsite calibration confirmation by use oftarget reflectors. The target reflectors should be mounted with identical physical displacement in both the offsite calibration facilities and the onsite mechanized equipment.
Each onsite periodic calibration should be preceded by complete system performance verification using a minimum of two (2) target reflectors separated by a distance representing 75 percent of maximum thickness to be examined.
b.
Written records of calibrations should be established for both target reflector responses and Code calibration block DAC curves for each transducer. These written records may be used to monitor driftsince the original recorded calibration.
C.
Measures should be taken to ensure that the different variables such as temperature, vibration, and shock limits are minimized by controlling packaging, handling, and storage.
File RG1.150 Page 9
SECOND INSPECTION INTERVAL PSLWG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1884 FPL requires calibration confirmation be performed at the frequency specified in paragraph 2 above and in compliance with the stability requirements of the Regulatory Guide. Vendors are required to perform the calibration confirmatio on site during using the basic calibration block, not an electronic block simulator. As such, the additional requirements identified in this paragraph for the use of an electronic block simulator do not apply.
In addition to periodic calibration confinnations functional checks of the UT instruments and the gain control circuitry system are typically performed at shift changeover.
These checks utilize electronic signal generators to monitor for changesin sweep and amplitude displays. The stabilitycriteria ofparagraph T-433 ofArtIcie 4 are used for acceptability of these functional checks.
For full vessel examinations using the SwRi Fast PaR
- systems, two Data Acquisitions Systems are utilized in parallel.
While one system is used for scanning and data acquisition, the other system is being calibrated for the next series of examinations.
In effect, two separate cable system are used, one for calibration and another forexaminations. SwRI's Remote Cable Calibrator system allo~s comparison of the diiference in cable performance and also provides electronic signal generation forperiodic verification that the performance ofthe two cable systems has not changed.
These cable performance checks are performed at the same time, and using the same criteria, as the electronic functional checks described above.
2.4 Calibratton Blocks Calibration blocks should comply with Appendix I to Section XI or Article 4,Section V of the ASME Code. When an alternative calibration block or a new conventional block is used, a ratio between the DAC curves obtained from the original block and from the new block should be noted (for reference) to provide for a meaningful comparison or previous and current data.
The calibration side-drilled holes in the basic calibration block and the block surface should be protected so that their characteristics do not change during storage. These side-drilled holes or the block surface should not be modified in any way (e.g., by polishing) between successive examinations.
Ifthe block surface or the calibration reflector holes have been polished by any chemical or mechanical means, this fact should be recorded.
File RG1.150 Page 10
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1894 3.0 EXAMINATlON The scope and extent of the ultrasonic examinations should comply with IWA-2000,Section XI, of the ASME Code.
If electronic gating is used to define the examination'olume within which indications are recorded the start and stop control points should Include the entire required thickness including the material near each surface.
If a single gate is used, it should be capable of recording multiple indications appearing in the gate. Alternative means of recording may be used providing they do not reduce flaw detection and recording capability.
Examination should be done with a minimum 25-percent scan overlap based on the transducer element size.
The scope and extent ofmanual examinations are addressedin the examination plan and examination procedure in accordance wifh IWA-2000.
In order to assure that the scope and extent ofaufomafed examinations comply with IlVA-2000 of Section XI, FPI requires the vendor to prepare a defailed Scan Plan for each automated examination activityin addition to typical examination procedures.
This plan addresses device configurations, scanning parameters, calibration parameters, gate seffings, and other speciiicinformation needed to perform the work. Implementation of fhe scan plan, as prepared for a specific application, willensure that the full volume of the ASME examination area are examined to the extent allowed by the vessel conligurafion. Coverageis accomplished using a combination ofseveral beam angles and examination techniques as specified in fhe scan plans.
The electronic gating system ufilized by vendors does not limifthe examination volume within whichindications are recorded. When the standard data acquisition systemis used, a video recovering is made of the acfual UTinsfrumenfs CRT presentations wifh the search unit positional informafion superimposed in real time.
The SwRI enhanced data acquisition system has overlapping electronic gating foreach UTchannel such that a fullvolume examinationis digitized, recorded, and displayed. The enhanced data acquisition system gafing is capable ofrecording mulfiple simultaneous indications.
Allexaminations performedin accordance with the regulatory guide are performed using a 25-percent overlap, unless a greater overlap is required.
File RG1.150 Page 11
SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 3.1 INTERNALSURFACE The capability to effectively detect defects at the internal clad/base metal interface shall be considered acceptable if the examination procedures(s) or techniques meet the requirements of section 6.0 of this document and demonstrates the following:
procedure for examination from the outer surface, or when using full vee from the inside surface, should include the use ofthe 2-percent notch which penetrates the internal (clad) surface of the calibration blocks, defined by Section XI, Appendix I, Figure l-3131, or Section V, Article 4, T-434-1.
Procedures forexamination from the internal surface when not using the full vee should conform to paragraph 3.1.b below.
b.
an alternate reflector, other than the 2-percent notch described above, may be used provided (1) that it is located at the clad/base metal interface or at an equivalent distance from the surface, (2) that it does not exceed the maximum allowable defect size, and (3) that equivalent or superior results can be demonstrated.
c.
the examination procedures should provide the volumetric examination of at least 1 inch of metal as measured perpendicular to the nominal location of the base metal cladding interface.
Procedures forexamination from the outside surface ofthe vessel walluse the 2-percent notch forreference as specifiedin paragraph 3.1(a). These procedures also include a half vee calibration with the notch used for calibration ofallindications which appear at the inside surface ofthe examination area.
Procedures fortandem examinations fiom the inside surface utilizes 1!16 inch diameter side-drilled holes at the clad/base metal interface as descnbed in paragraph
- 3. 1(b). In both cases, procedures provide for volumetric examination ofgreater than 1-inch depth below the claddinginterface as required byparagraph 3.1(c). SwRI has demonstrated that the reference sensitivity established on the 1!16 inch diameter side drilled holes meets or exceeds that specified in Section XIofthe ASME Code. This technique has also been demonstrated to have the capabi%ty of detecting flaws with good signal-to-noise discrimination at depths ofat least 2-3!4 inches below the clad-to-base metal interface, thus overiapping the through-wall zone of calibrated sensitivity of the 45 degree and 60 degree beams. Using the tandem beam transducers, SwRI has detected flaws ofminute size in the area between the clad-to-base metal interface and the first 45 degree and 60 degree dac point.
File RG1.150 Page 12
"I SECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVIsION 0 REGULATORY GUIDE 1.150 September 28, 1994 FPL has also used 70 degree dual (side-by-side mounted piezoelectric elements) search units for underclad examinations; however, the useful range is limited to approximately 1 inch of depth below the cladding with no discernible improvement over the tandem beam search unit at the clad-to-base metal interface.
3.2 ScannIng Weld-Metal Interface The beam angles used to scan welds should be based on the geometry of the weld/parent metal interface. Where feasible for welds such as those Identified in Section T-441.4.2 of Article 4,Section V, of the ASME Code, at least one angle should be such that the beam is perpendicular
(+ or - 15 degrees to the perpendicular) to the weld/parent metal interface, or should be demonstrated that unfavorably orientated planar flaws can be detected by UT technique being used.
lfthis is not feasible, use of alternative volumetric NDE techniques, as permitted by the ASME Code, should be considered.
For RPV shell seam welds, FPL uses the nominal Code-specified 0<egree, 4°ree, and 60<egree, beams to examine the full volume of the wall section except for the volume ofmaterial near the beam entry point, forwhich we use the previously mentioned tandem search units.
Section T-441.4.2 (or T-441.3.2.2 ofArticle 4,Section V, states that beam angles other than O-degree, 45-degree, and 60-degree should be used for the examination of (a) flange welds when fhe examinafion is conducfed from the flange face, (b) nozzle and nozzle welds when fhe examinafion is conducted, from fhe nozzle bore, (c) attachment and support welds, and (d) examinafion ofdouble faperjuncfions, FPL has employed this approach for many years.
FPL and FPL approved vendors procedures, however, often provide more than Code-specified coverage where feasible. Each offhe unique weld configurations nofed above is evaluafed to determine the best and most comprehensive coverage affainable. Mfhere necessary, other angle and straight beam examinations are performed fo assure complete coverage ofnozzle-to-shell, vessel-fo-fiange, and affachmen welds. P 8 viouslyment/oned tandem beam techniques are also utilized to provide the required near surface coverage when nozzle bore examinations are performed.
4.
BEAM PROFILE Delete entire paragraph. This section included in Recommended Change 1.2.f, Angle 8earri Profile Characterization.
File RG1.150 Page 13
tSECOND INSPECTION INTERVAL PSL-RG 1.150 IMPLEMENTATIONOF REVISION 0 REGULATORY GUIDE 1.150 September 28, 1994 5.
SCANNING WELD-METALINTERFACE 6.
Delete entire paragraph.
This section Included in Recommended Change 3.2, Scanning Weld-Metal Interface.
RECORDING AND SIZING The capability to detect, record, and size the flaws delineated by Section XI, IWB-3500, should be demonstrated. The measurement tolerance established should be applied when sizing flaws detected and recorded during scanning (see paragraph 7.a).
The difference befween joint configuration, plate thicknesses, fiaw locations within the we/d, fiaw orientafions, and acousfic characferisfics of the component mafenal a/I contnbufe to the inherent variabilityofsizing techniques. FPL has used and willcontinue to use, Code and non-Code sizing techniques, the use ofsupplemental NOE techniques ifpracfical, mockups of the particular configuratio, and when required, consultanfs to fullyevaluafe fhe examination and the results.
6.1 Geomehh Indicathns Indications determined to be from geometric sources need not be sized.
Recording of these indications should be at 50-percent DAC. When indications are evaluated as geometric in origin, the basis for that determination should be described. After recording sufficient information to identify the origin of the geometric indication, further recording and evaluation are not required.
Indication analysis and sizing are performed by FPL or FPL approved vendors. All the examination data is given an administrative and technical review by a FPL qualified NDE Level II andlor Level III, cerfr'fied in that particular method.
Indications that are geomefricin origin an: recorded at 50-percent DAC and the nature of each such indication is documenfed.
6.2 indications with Changing Metal Path Indications that change metal path distances (including through-wall dimension), when scanned in accordance with the requirements of ASME Section XIfor a distance greater than that recorded from the calibration reflector, should be recorded.
File RG1.150 Page 14
SECOND INSPECTION INTERVAL PSLWG 1.150 IMPLEMENTATIONOF REVISION 0 REGUIATORY GUIDE 1.150 September 28, 1994 b.
Reflectors which are at metal paths representing 25 percent and greater of the through-wall thickness of the vessel wall measured from the inner surface should be recorded in accordance with the requirements of the ASME Section XI and characterized at 50-percent DAC.
Reflectors which are within the inner 25 percent of the through-wall thickness should be recorded at 20 percent DAC. Characterization should be in accordance with the demonstrated methods under paragraph 6.0. When the indication is sized at 20 percent DAC, this size may be corrected by subtracting the beam width in the through-thickness direction obtained from the calibration hole (between 20 percent DAC points) which is at a depth similar to the flaw depth. If the indication exceeds 50 percent DAC, the length should be recorded by measuring the distance between 50 percent DAC levels.
The determined size should be the larger of the two.
FPL believes that theintent ofthis paragraphis to require the examiner to determine and document the most accurate size of a refiector having through-wall dimension, to the extent practicable.
FPL typically requires both 20 percent and 50 percent beam spread measurement at the time of calibration in case the information is required during data analysis.
For tandem beam search units, the use ofbeam spread conection forsizing is not normally applicable because of the unique beam profile characteristics.
When near surfaceindications are observed during a vessel examination, FPL routinely applies one or more special sizing techniques, before comparing the size to the acceptance criteria of Secfion XI.
In general, FPL concurs with the specified approach, but also requires application ofselected alternate sizing techniques when necessary based upon a
case-by-case evaluation in determining which technique is considered most appropriate for the anticipated flaw type and orientatio.
6.3 Indication WIthout Changing Metal Path a.
Indications which do not change metal path distance when scanned in accordance with the requirements of ASME Section XI and are within the outer 75 percent of the through-wall dimension should be recorded when any continuous dimension exceeds 1 inch.
File RG1.150 Page 15
SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGULATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1884 b.
Ifthe indication falls within the inner 25 percent of the through-wall dimensions, it should be recorded ar 20 percent DAC and evaluated at 50 percent DAC.
c.
Precautionary note: Indications lying parallel to welds may appear nontraveling (without changing metal path) when scanned by parallel moving transducers whose beams are aimed normal to the weld, i.e.,
at SO degrees.
Multiple scans,
- however, may reveal that these indications are traveling indications. If so, recording and sizing are to be done in accordance with paragraph 6.2.
To the extent pracficable, evaluation ofnontravelingindicafionsis per/ormed in accordance with these requirements, along with the use of additional sizing techniques where appropriate.
The precautionary note ofparagraph 6.3.cis appropriate.
To alleviafe this concern, scanning is performed in the direction of the beam component wherever possible.
In those instances when this preferred mode of scanning cannot be utilized, NDE procedures address this concern by requiring additional scans (along the sound beam direction) of any nongeomefric angle beam indication observed during scans made parallel fo the weld. Additionalscans are performed using small scanincrements(or
/arge transducer overiap) in order to develop a very accurate data sef.
6.4 Additional Recording Criteria The followinginformation should also be recorded forindications that are reportable according to this regulatory position:
a, Indications should be recorded at scan intervals no greater than 1/4 inch.
b.
The recorded information should Include the indication travel (metal path distance) and the transducer position for 20 percent (where applicable), 50 percent, and 100 percent DAC and the maximum amplitude of the signal.
File RG1.150 Page 16
SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGUlATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1994 When multichannel equipment is used in the examination system such as that all examination displays are not available for simultaneous viewing, an electronic gating system should be used which will provide on-line, reportable,
'recorded information regarding metal path, amplitude, and position of all indications exceeding a preset level. The preset level should be the minimum recording level required. To ensure that all recordable indications are
- recorded, a preferred method would incorporate multigates in each channel or a single gate for each channel with multI-Indication recording capability.
In reference fo Paragraph 6.4.a, initial scanning is af 25 percent overiap as specr'fied iParagraph 3. However, data to be utilized for specific sizing or invesfigation of indicafions that exceed the allowable limifsof Section XIis acquired at 1/4 inch scan intervals.
The information required in Paragraph 6.4.b is typicallyrecorded for all vessel examinafions, whether the examination is performed manually or using automated equipment.
In reference fo Paragraph 6.4.c which addresses the use ofmulti-channel equipmenf, the standard data acquisition system utilized by SeRI satisfie this requirement by virtue ofthe video recordr'ng offhe
~ instrument screens. Since fhe entire screen presentationis recorded, simulfaneousmultiplesignalsarerecorded asencountered.
Thedafa analysis pmcess also includes review of all of the video tape dafa thereby ensuring that each recorded signal is reviewed and
.analyzed.
7.
REPORTING OF RESULTS Records obtained while followingthe recommendations of regulatory position 1.2, 3, and 6, along with discussions and explanations, ifany, should be kept available at the site. Ifthe size of an indication, as determined in regulatory position 6.2 or 6.3, exceeds the allowable limits of Section XI of the ASME Code, the indications should be reported as abnormal degradation of reactor pressure boundary in accordance with the recommendation of regulatory position 2.a(3) of Regulatory Guide 1.16.
Fife RG1.150 Page 17
SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGULATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1984 Along with the report of ultrasonic examination test
- results, the following information should also be included:
a.
The best estimate of the tolerances in sizing the flaws at the Sensitivity required in Section 6 and the basis for this estimate.
This estimate may be determined in part by the use of additional reflectors in the basic calibration block.
b.
A description of the technique used to qualify the effectiveness of the examination procedure, including, as a
- minimum, material, section thickness, and reflectors.
The best estimates of the portion of the volume required to be examined by the ASME Code that has not been effectively examined such as volumes of material near each surface because of near-field or other effects, volumes near interfaces between cladding and parent metal, volumes shadowed by laminar defects, volumes shadowed by part geometry, volumes inaccessible to the transducer, volumes affected by electronic gating, and volumes near the surface opposite the transducer.
Sketches and/or descriptions ofthe tools, fixtures, and component geometry which contribute to incomplete coverage should be included.
d.
Provide sketches of equipment (i.e., scanning mechanism and transducer holders) with reference points and necessary dimensions to allow a reviewer to follow the equipment's indication location scheme.
e.
When other volumetric techniques are used, a description ofthe techniques used should be included in the report.
In reference to Paragraph 7.a, FPL feels that the sizes obtained using Code sizing techniques should be used consistently for companson to Code acceptance standards whenever possible.
Based on experience, Code sizing techniques appear to be somewhat conservative; however, there is little evidence to support the feasibilityofdeveloping specific tolerances orcorfection factors forCode sizing techniques. Noris there signiiicant evidence ofimproved accuracy and consistency resulting from the use of any one alternate sizing technique.
Alternate sizing methods must be used carefully and, in effect, should be used only when it can File RG1.150 Page 18
SECOND INSPECTION INTERVAL IMPLEMENTATIONOF REGULATORY GUIDE 1.150 PSL-RG 1.150 REVISION 0 September 28, 1994 be determined that the Code sizing techniques are, forsome reason, inappropriate for the specific type offlaw encounten:d.
These statements do point out that flaw sizes based on UT are estima'tes. FPL, ofcourse, has vaporing degrees ofconfidence in flawsize estimates depending on pertinent examination variables. Since the ramificafions ofour flaw'size estimates are very great, FPL willtypicallyrecommend certain actions fo our vendors which can increase our confidencein flawsize estimation. These recommendations may include actions such as:
(a) placing additional holes in the calibration block (b)
'constructing mockups of fhe examination an:a (c) using other NDE equipment (d) applying alternate NDE methods (e) perl'orming certain laboratory tests (fl calling in specialists with particular experience in. similar problems.
In reference to Paragraph 7.b, procedure qualifications are required and the documentationis reviewed byFPL priorto perl'ormance ofthe examination activity.
Documentationis available forreview byfhe enforcement and regulatory authority, and the authorized inspection agency at any time.
In reference to Paragraph 7'.c, FPL requires a detailed limitations report for all reactor vessel examinations.
The report is usually a combination of tables and sketches that quantify the various limitations fo the Code required volume.
The information identifiedin Paragraph 7'.dis required by FPL to beincluded in a final report of the examination activity.
In reference to Paragraph T.e, when alternate techniques are utilized, either for examination or sizing purposes, a complete description of the application and results is included within the final report.
File RG1.150 Page 19
t NUCLEAR EKQINEERINQ CSIWODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 88408 (407) ~181
'T. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINArlON PSL4004C)A444 Revision 0 Sepiembor 28, 1884 ATTACHMENTB PERCENT OF EXAMINATIONCOVERAGE Examlnathn Area Identlficathn Lower Head-to--
Lower Shell Circ.
Weld No. 201-141 Beam Angle 0 IAM 45 60 50/704 0 WRV 4A'PT 50/7lPT Beam DIrectIon UP/DN UP/DN UP/DN CWICCW CWICCW CWICCW Percent Coverage 93%
10m86%
100/88%
100/84%
93%
93%
93%
93%
FIgure No.
Descripthn of Examlnathn Coverage and umltathns Examination of IWB-25004 E F~ volume limited along length ofweld below core barrel anfntation lugs.
Claimed coverage Is 93%
overall Lower Shell-to-Intermediate Shell Circ. Weld No. 101-171 0 LAM 45'0'0/70RV 45'T 60'T 50/70'T UP/DN UP/DN UP/DN CWICCW CWICCW CWICCW 92%
92%
92%
92%
85%
85%
85%
83%
Examination of IWB-2500-2 A-BC-D volume limited along length ofweld near vessel material specimen tubes.
Claimed coverage is 88%
overall Upper Shell-to-Middle Shell Circ.
Weld No. 106-121 Intermediate Shell Long. Weld e15 Deg.
No. 101-124A RAM 45 60 50/70 NNRV 4A'PT 50/70 O'am 45'0'0/70RV 45'T 60'T 50/70'T UP/DN UP/DN UP/DN CW/CCW CW/CCW CWICCW CWICCW CWICCW CWICCW UP/DN UP/DN UP/DN 100ok 100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100ok 100%
100ok None None None None None None None None None None None None None None None None IWB-2500-1 A44-D-volume examined for 100% weld length without limitation.
Claimed coverage is 100%
overall Examination of IWB-2500-2 A-B~ examined for 100%
weld length without limitation.
Claimed coverage is 100%
overall File LISNRCAOA Page 12
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'SI NUCLEAR ENQINEERINQ CSIODE PROGRAMS P,.O. BOX 14000 JUNO BEACH, FLA 33408 (407) B$44181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORRATION OF ALTERNATIVE EXAMINATION PSL400~A44 1 Revtohn 0
September 28, 1884 Examlnathn Aiba Identlflcathn Intermediate Shell Long. Weld @135 Deg.
No. 101-124B Intermediate Shell Long. Weld 255 Deg.
No. 101-124C Upper Shell Longitudinal Weld O15 Deg.
No. 101-122A Upper Shell Longitudinal Weld O135 Deg.
No. 101-122B Upper Shell Longitudinal Weld O255 Deg.
No. 101-122C Beam Angle oo Lam 45'0'N70' WRV 45'T 60'T 50/70'T 0 Lam 45'0'0/70 O'RV 45'T 60'T 5N70'T 0 Lam 45'0'0nORV 45'T 60'T 50/70'T 0 Lam 45'0'0/70RV 45'T 60'T 50/70'T O'am 45'0'0nORV 45'T 60'T 50/70'T Beam Dlrecthn CWICCW CWICCW GW/CCW UP/DN UP/DN UP/DN GWICCW GWICGW CWICCW UP/DN UP/DN UP/DN CWICCW CWICCW CWICGW UPIDN UP/DN UPIDN CWICCW CWICCW CW/CCW UP/DN UP/DN UP/DN CW/CCW GWICCW CWICCW UP/DN UP/DN UP/DN Percent Coverage 100%
100%
100%
100%
100%
100%
100%
100%
74%
100%/70%
100%/55%
100%/74%
100%
100%
100%
100%
95%
100%/96%
100%N6%
100%99%
97%
79%
74%
95%
96%
100%/98%
100%/98%
100%
98%
87%
83%
97%
96%
100%NB%
100%98%
100%
98%
87%
83%
97%
Figum NO.
None None None None None None None None 185 DescrIpthn of Examlnathn Coverage and Umltathns Examination of IWB-2500-2 A
~ examined for 100%
weld length without limitation.
Claimed coverage Is 100%
overall Examination of IWB-2500-2 A-B~D volume limited from one side along length ofweld near vessel material specimen tubes. Claimed coverage is 87% overall Examination of IWB-2500-2 A-B~ volume was limited at Intersection with the adjacent outlet nozzle integral extension. Claimed coverage Is 92% overall Examination of IWB-2500-2 A-BN-D volume was limited at lnterseclion with the adjacent inlet nozzle inner blend.
Claimed coverage is 94%
overall Examination of IWB-2500-2 A-
~ volume was limited at intersection with the adjacent inlet nozzle Inner blend.
Claimed coverage is 94%
overall File USNRCAOA Page 13
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Ilgwu 1SI NUCLEAR ENQINEERINQ CSINODE PROQRAMS P,O. BOX 14000 JUNO BEACH, FLA 88408 (407) 8944181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400447A44 1
Revision 0 SePtimber 28, 1994 Examlnatlon Area identification Beam
'eam Angle Direction Percent Coverage Figure NO.
Descrfptlon of Examination Coverage and Umhttlons Lower Shell Longitudinal Weld O15 Deg. No.
101-142A Lower Shell Longitudinal Weld
@135 Deg. No.
101-142B Lower Shell Longitudinal Weld 225 Deg. No.
101-142C 0 LAM 45I 50/70 0 WRV 4W QFT 50/70'r 0 LAM 45 80 50/70 0 WRV 4W QPT 50/7O'r 0 I%M 45I 50/70'NRV 4W SPT 50/70T CWICCW CWICCW CWICCW UP/DN UP/DN UP/DN CWICCW CWICCW CWICGW UP/DN UP/DN UP/DN GWICCW CWICGW CW/CCW UP/DN UP/DN UP/DN 100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
87%
100%/85%
100%/77%
100%/87%
100%
100%
100%
100%
None None None None None None None None None None None None None None None None Examination of IWB-2500-2 A-
~ examined for 100%
weld length without limitation Examination of IWB-2500-2 A-BC-D examined for 100%
weld length without limitation Examination of IWB-2500-2 A-BN volume limited from one side along length of weld near reactor vessel material sPecimen tubes. Claimed coverage Is 93% overall File USNRCAOA Page 14
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NUCLEAR ENQINEERINQ CSI&ODE PROGRAMS PO. BOX 14000 JUNO BEACH, FLA 88408 (407) 68~181 RRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PSL400 JC)A4I4-1 RevteIen 0
September 28, 1884 ATTACHMENTC EXAMINATIONLIMITATION DRAWINGS File USNRCA,OA Page 15
2-LEAK MONITOR TUBES 172-103A e 16s.
172-103B e
345'UTLET NOZZLE INNER RADIUS AREA ON-IR-A e O'OCATIO QN-IR-B e
180 LOCATI 101-122-A 101-122-B 101-122-C INLET NOZZLE INNER RADIUS AREA IN-IR-A e 60 LocATION IN-IR-B e 120'OCATION IN-IR-C e 240'OCATION IN-IR-D e 300'OCATION 103-151-A e 10'OCATION 103-1$ 1-B e 40'OCATION 101-124-A 101-124-B 106-121 101-171 2998-4395 REV.
1 E-71172-171-002 REV. 0 E-71172-171-008 REV. 0 103-1$ 1-C e 8s LocATION 103-151-D e 135'OCATION 103-151-E e 160'OCATION 103-151-F e 205'OCATION 103-151-G e 250'OCATION 103-151-H e 280'OCATION 103-151-I e 325'OCATIO CORE STOP LUG 101-122-C 101-142-A 101-142-B I
101-142-C t
FLOV BAFFL FB-01 201-141 CORE STABILIZING LUG (SNUBBER) 101-141-A e O'OCATION 101-141-B e
60 LocATION 101-141-C e 120'ocATIQN 101-141-D e 180'OCATION 101-141-E e 240'OCATION 101-141-F e 300'OCATION
~i SECTION A-A-SEE DMG. 02-001-B SECTION B-B-SEE DMG.02-001"B SECTION X-X-SEE DVG. 02-001-C SECTION Y"Y-SEE DVG. 02-001-C SECTION Z-Z-SEE DVG. 02-001-C REFERENCE DRAVINGS E-71172-121-001 REV. 4 E-71172-124-001 REV. 5 E-71172-141-001 REV. 2 E-71172-141-002 REV. 6 E-71172-142-001 REV. 7 E-71172-151-001 REV. 5 E-71172-154-001 REV, 4 NOTES CALIBRATION BLOCKS AND HATERIAL 2-LEAK HONITOR TUBES AND FITTINGS <SB-166)
UT-I, UT-2. UT-10 DATE< 9/28/94 ELA ZONEi I DRA VII'b ISI SKETCH 02 001 REVl$104 2
FLORIDA PQVER L LIGHT ST. LUCIE UNIT 2 TITLEiREACTOR PRESSURE VESSEL
0'5' I
I 60'0' I
120'35'I I
180'40'55'70' 101-121 300'60' AREA OF ID TAPER NOZZLE INTERFERENCE WITH VERTICAL WELD TRANSVERSE SCANS 101-122A
~ 101-1228
~ 106-121 ~ 101-122C RPV MATERIAL SPECIMEN TUBES 101-124A
~ 101-1248 101-124C 33'53'3
~ 101-171 00 101-142A 60'20'3'7'04' 101-1428 O
180'40'77'84'63~ 101-142C 300'60'LOW SKIRT SUPPOR CORE BARREL ANTI ROTATION LUG 10'0'01-154A 40'5 90'01-1548 130 150 101-154C 160'05'10'01-154D 250 270'01-154E 280'25'30'01-154F FLOW SKIRT UPPER EDGE FLOW SKIRT LOWER EDGE ROLL OUT INSIDE VIEW INACCESSIBLE SCANNING SURFACES 101-151 FIGURE 1.1 REACTOR PRESSURE VESSEL ROLL OUT VIEW
RPV MATERIAL SPECIMEN INTERMEDIATE AND LOWER SHELL VERllCAL WELOS AT 255'ESSEL AZIMUTH PARALLEL EXAMINATION UMITATION (0,'5, 60, 50/70'CW BEAMS)
FIGURE 1.5 VERTICAL WELD UMITAllONS
na os
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NUCLEAR ENGINEERING CSINODE PROGRAMS P.O. BOX 14000 JUNO BEACH, FLA 53408 (407) 8844181 ST. LUCIE UNIT2 FIRST INSERVICE INSPECTION INTERVAL REQUEST FOR AUTHORIZATION OF ALTERNATIVE EXAMINATION PS L4004OA4I4-1 Revkbn 0
SepIember 28, 1884 END OF DOCUMENT Fite USNRCAOA Page 16
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